log bind parameter values on error

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index f64402a..924a76c 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6270,6 +6270,23 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters" xreflabel="log_parameters">
+      <term><varname>log_parameters</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether the statement is logged with bind parameter values. 
+        It adds some overhead, as postgres will cache textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged. The default is
+        <literal>off</literal>. Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index a98c836..9ee3954 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -404,6 +404,7 @@ EvaluateParams(PreparedStatement *pstmt, List *params,
 	paramLI->parserSetup = NULL;
 	paramLI->parserSetupArg = NULL;
 	paramLI->numParams = num_params;
+	paramLI->hasTextValues = false;
 
 	i = 0;
 	foreach(l, exprstates)
diff --git a/src/backend/executor/functions.c b/src/backend/executor/functions.c
index de41588..195e3c5 100644
--- a/src/backend/executor/functions.c
+++ b/src/backend/executor/functions.c
@@ -921,6 +921,7 @@ postquel_sub_params(SQLFunctionCachePtr fcache,
 			paramLI->parserSetup = NULL;
 			paramLI->parserSetupArg = NULL;
 			paramLI->numParams = nargs;
+			paramLI->hasTextValues = false;
 			fcache->paramLI = paramLI;
 		}
 		else
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 94a53e0..398f0e3 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -2399,6 +2399,7 @@ _SPI_convert_params(int nargs, Oid *argtypes,
 		paramLI->parserSetup = NULL;
 		paramLI->parserSetupArg = NULL;
 		paramLI->numParams = nargs;
+		paramLI->hasTextValues = false;
 
 		for (i = 0; i < nargs; i++)
 		{
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index a89a25e..5aebd428 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -31,6 +31,8 @@
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * We don't copy textual representations here.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -53,6 +55,7 @@ copyParamList(ParamListInfo from)
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
 	retval->numParams = from->numParams;
+	retval->hasTextValues = false;
 
 	for (i = 0; i < from->numParams; i++)
 	{
@@ -229,6 +232,7 @@ RestoreParamList(char **start_address)
 	paramLI->parserSetup = NULL;
 	paramLI->parserSetupArg = NULL;
 	paramLI->numParams = nparams;
+	paramLI->hasTextValues = false;
 
 	for (i = 0; i < nparams; i++)
 	{
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 0c0891b..1f81fba 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -86,6 +86,12 @@
  */
 const char *debug_query_string; /* client-supplied query string */
 
+/*
+ * The top-level portal that the client is immediately working with:
+ * creating, binding, executing, or all at one using simple protocol
+ */
+Portal current_top_portal = NULL;
+
 /* Note: whereToSendOutput is initialized for the bootstrap/standalone case */
 CommandDest whereToSendOutput = DestDebug;
 
@@ -183,7 +189,7 @@ static void forbidden_in_wal_sender(char firstchar);
 static List *pg_rewrite_query(Query *query);
 static bool check_log_statement(List *stmt_list);
 static int	errdetail_execute(List *raw_parsetree_list);
-static int	errdetail_params(ParamListInfo params);
+static int	errdetail_params(Portal portal);
 static int	errdetail_abort(void);
 static int	errdetail_recovery_conflict(void);
 static void start_xact_command(void);
@@ -1694,6 +1700,9 @@ exec_bind_message(StringInfo input_message)
 	else
 		portal = CreatePortal(portal_name, false, false);
 
+	Assert(current_top_portal == NULL);
+	current_top_portal = portal;
+
 	/*
 	 * Prepare to copy stuff into the portal's memory context.  We do all this
 	 * copying first, because it could possibly fail (out-of-memory) and we
@@ -1731,6 +1740,9 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* GUC value can change, so we remember its state to be consistent */
+		bool need_text_values = log_parameters;
+
 		params = (ParamListInfo) palloc(offsetof(ParamListInfoData, params) +
 										numParams * sizeof(ParamExternData));
 		/* we have static list of params, so no hooks needed */
@@ -1741,6 +1753,8 @@ exec_bind_message(StringInfo input_message)
 		params->parserSetup = NULL;
 		params->parserSetupArg = NULL;
 		params->numParams = numParams;
+		/* mark as not having text values before we have populated them all */
+		params->hasTextValues = false;
 
 		for (int paramno = 0; paramno < numParams; paramno++)
 		{
@@ -1807,9 +1821,31 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				if (pstring)
+				{
+					if (need_text_values)
+					{
+						if (pstring == pbuf.data)
+						{
+							/*
+							 * Copy textual representation to portal context.
+							 */
+							params->params[paramno].textValue =
+															pstrdup(pstring);
+						}
+						else
+						{
+							/* Reuse the result of encoding conversion for it */
+							params->params[paramno].textValue = pstring;
+						}
+					}
+					else
+					{
+						/* Free result of encoding conversion */
+						if (pstring != pbuf.data)
+							pfree(pstring);
+					}
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1835,6 +1871,22 @@ exec_bind_message(StringInfo input_message)
 							(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
 							 errmsg("incorrect binary data format in bind parameter %d",
 									paramno + 1)));
+
+				/*
+				 * Compute textual representation for further logging. We waste
+				 * some time and memory here, maybe one day we could skip
+				 * certain types like built-in primitives, which are safe to get
+				 * it calculated later in an aborted xact.
+				 */
+				if (!isNull && need_text_values)
+				{
+					Oid			typoutput;
+					bool		typisvarlena;
+
+					getTypeOutputInfo(ptype, &typoutput, &typisvarlena);
+					params->params[paramno].textValue =
+								OidOutputFunctionCall(typoutput, pval);
+				}
 			}
 			else
 			{
@@ -1859,10 +1911,22 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/*
+		 * now we can safely set it, as we have textValue populated
+		 * for all non-null parameters
+		 */
+		params->hasTextValues = need_text_values;
 	}
 	else
 		params = NULL;
 
+	/*
+	 * Set portal parameters early for them to get logged if an error happens
+	 * on planning stage
+	 */
+	portal->portalParams = params;
+
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
@@ -1936,13 +2000,14 @@ exec_bind_message(StringInfo input_message)
 							*portal_name ? portal_name : "",
 							psrc->query_string),
 					 errhidestmt(true),
-					 errdetail_params(params)));
+					 errdetail_params(portal)));
 			break;
 	}
 
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -1961,7 +2026,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 	char		completionTag[COMPLETION_TAG_BUFSIZE];
 	const char *sourceText;
 	const char *prepStmtName;
-	ParamListInfo portalParams;
 	bool		save_log_statement_stats = log_statement_stats;
 	bool		is_xact_command;
 	bool		execute_is_fetch;
@@ -1978,7 +2042,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 		ereport(ERROR,
 				(errcode(ERRCODE_UNDEFINED_CURSOR),
 				 errmsg("portal \"%s\" does not exist", portal_name)));
-
 	/*
 	 * If the original query was a null string, just return
 	 * EmptyQueryResponse.
@@ -2005,21 +2068,22 @@ exec_execute_message(const char *portal_name, long max_rows)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
-		/*
-		 * An xact command shouldn't have any parameters, which is a good
-		 * thing because they wouldn't be around after finish_xact_command.
-		 */
-		portalParams = NULL;
 	}
 	else
 	{
+		/*
+		 * We do it for non-xact commands only, as an xact command
+		 * 1) shouldn't have any parameters to log;
+		 * 2) may have the portal dropped early.
+		 */
+		Assert(current_top_portal == NULL);
+		current_top_portal = portal;
+
 		sourceText = portal->sourceText;
 		if (portal->prepStmtName)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
-		portalParams = portal->portalParams;
 	}
 
 	/*
@@ -2071,7 +2135,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 						*portal_name ? portal_name : "",
 						sourceText),
 				 errhidestmt(true),
-				 errdetail_params(portalParams)));
+				 errdetail_params(portal)));
 		was_logged = true;
 	}
 
@@ -2160,13 +2224,14 @@ exec_execute_message(const char *portal_name, long max_rows)
 							*portal_name ? portal_name : "",
 							sourceText),
 					 errhidestmt(true),
-					 errdetail_params(portalParams)));
+					 errdetail_params(current_top_portal)));
 			break;
 	}
 
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2304,63 +2369,20 @@ errdetail_execute(List *raw_parsetree_list)
  * Add an errdetail() line showing bind-parameter data, if available.
  */
 static int
-errdetail_params(ParamListInfo params)
+errdetail_params(Portal portal)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
-	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
-
-		pfree(param_str.data);
+	/* Make sure any trash is generated in MessageContext */
+	MemoryContext oldcontext = MemoryContextSwitchTo(MessageContext);
+	char *params_message = get_portal_bind_parameters(portal);
 
-		MemoryContextSwitchTo(oldcontext);
+	if (params_message)
+	{
+		errdetail("parameters: %s", params_message);
+		pfree(params_message);
 	}
 
+	MemoryContextSwitchTo(oldcontext);
+
 	return 0;
 }
 
@@ -2678,6 +2700,94 @@ drop_unnamed_stmt(void)
 	}
 }
 
+/*
+ * get_portal_bind_parameters
+ * 		Get the string containing parameters data, is used for logging.
+ *
+ * Can return NULL if there are no parameters in the portal
+ * or the portal is not valid, or the text representations of the parameters are
+ * not available. If returning a non-NULL value, it allocates memory
+ * for the returned string in the current context, and it's the caller's
+ * responsibility to pfree() it if needed.
+ */
+char *
+get_portal_bind_parameters(Portal portal)
+{
+	ParamListInfo params;
+	StringInfoData param_str;
+
+	/* Fail if no current portal */
+	if (!PortalIsValid(portal))
+		return NULL;
+
+	params = portal->portalParams;
+
+	/* No parameters to format */
+	if (!params || params->numParams == 0)
+		return NULL;
+
+	/*
+	 * We either need textual representation of parameters pre-calcualted,
+	 * or call potentially user-defined I/O functions to convert internal
+	 * representation into text, which cannot be done in an aborted xact
+	 */
+	if (!params->hasTextValues && IsAbortedTransactionBlockState())
+		return NULL;
+
+	initStringInfo(&param_str);
+
+	/* This code doesn't support dynamic param lists */
+	Assert(params->paramFetch == NULL);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *prm = &params->params[paramno];
+		char	   *pstring;
+		char	   *p;
+
+		appendStringInfo(&param_str, "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (prm->isnull)
+		{
+			appendStringInfoString(&param_str, "NULL");
+			continue;
+		}
+
+		if (params->hasTextValues)
+			pstring = prm->textValue;
+		else
+		{
+			Oid			typoutput;
+			bool		typisvarlena;
+
+			if (OidIsValid(prm->ptype))
+			{
+				appendStringInfoString(&param_str, "UNKNOWN TYPE");
+				continue;
+			}
+
+			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
+			pstring = OidOutputFunctionCall(typoutput, prm->value);
+		}
+
+		appendStringInfoCharMacro(&param_str, '\'');
+		for (p = pstring; *p; p++)
+		{
+			if (*p == '\'') /* double single quotes */
+				appendStringInfoCharMacro(&param_str, *p);
+			appendStringInfoCharMacro(&param_str, *p);
+		}
+		appendStringInfoCharMacro(&param_str, '\'');
+
+		if (!params->hasTextValues)
+			pfree(pstring);
+	}
+
+	return param_str.data;
+}
+
 
 /* --------------------------------
  *		signal handler routines used in PostgresMain()
@@ -4031,10 +4141,11 @@ PostgresMain(int argc, char *argv[],
 		EmitErrorReport();
 
 		/*
-		 * Make sure debug_query_string gets reset before we possibly clobber
-		 * the storage it points at.
+		 * Make sure these get reset before we possibly clobber
+		 * the storages they point at.
 		 */
 		debug_query_string = NULL;
+		current_top_portal = NULL;
 
 		/*
 		 * Abort the current transaction in order to recover.
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 8b4720e..6f4ab5a 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -76,6 +76,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 #include "utils/ps_status.h"
 
 
@@ -344,6 +345,7 @@ errstart(int elevel, const char *filename, int lineno,
 		{
 			error_context_stack = NULL;
 			debug_query_string = NULL;
+			current_top_portal = NULL;
 		}
 	}
 	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
@@ -2788,6 +2790,16 @@ write_csvlog(ErrorData *edata)
 	if (print_stmt && edata->cursorpos > 0)
 		appendStringInfo(&buf, "%d", edata->cursorpos);
 	appendStringInfoChar(&buf, ',');
+	if (print_stmt)
+	{
+		char *param_values = get_portal_bind_parameters(current_top_portal);
+		if (param_values != NULL)
+		{
+			appendCSVLiteral(&buf, param_values);
+			pfree(param_values);
+		}
+	}
+	appendStringInfoChar(&buf, ',');
 
 	/* file error location */
 	if (Log_error_verbosity >= PGERROR_VERBOSE)
@@ -2944,6 +2956,17 @@ send_message_to_server_log(ErrorData *edata)
 		appendStringInfoString(&buf, _("STATEMENT:  "));
 		append_with_tabs(&buf, debug_query_string);
 		appendStringInfoChar(&buf, '\n');
+
+		if (log_parameters)
+		{
+			char *param_values = get_portal_bind_parameters(current_top_portal);
+			if (param_values != NULL)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("PARAMETERS:  %s\n"), param_values);
+				pfree(param_values);
+			}
+		}
 	}
 
 #ifdef HAVE_SYSLOG
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 7eda7fd..f072741 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -464,6 +464,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1235,6 +1236,15 @@ static struct config_bool ConfigureNamesBool[] =
 		NULL, NULL, NULL
 	},
 	{
+		{"log_parameters", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters,
+		false,
+		NULL, NULL, NULL
+	},
+	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
 			NULL
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index f7c1dee..6d8bdc0 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -526,6 +526,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters = off			# log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c
index a92b454..62107d8 100644
--- a/src/backend/utils/mmgr/portalmem.c
+++ b/src/backend/utils/mmgr/portalmem.c
@@ -24,6 +24,7 @@
 #include "miscadmin.h"
 #include "storage/ipc.h"
 #include "utils/builtins.h"
+#include "utils/lsyscache.h"
 #include "utils/memutils.h"
 #include "utils/snapmgr.h"
 #include "utils/timestamp.h"
@@ -53,6 +54,7 @@ typedef struct portalhashent
 
 static HTAB *PortalHashTable = NULL;
 
+
 #define PortalHashTableLookup(NAME, PORTAL) \
 do { \
 	PortalHashEnt *hentry; \
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index ded3b3a..3b850a4 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -93,6 +93,7 @@ typedef struct ParamExternData
 	bool		isnull;			/* is it NULL? */
 	uint16		pflags;			/* flag bits, see above */
 	Oid			ptype;			/* parameter's datatype, or 0 */
+	char	   *textValue;		/* textual representation for debug purposes */
 } ParamExternData;
 
 typedef struct ParamListInfoData *ParamListInfo;
@@ -116,6 +117,8 @@ typedef struct ParamListInfoData
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
 	int			numParams;		/* nominal/maximum # of Params represented */
+	bool		hasTextValues;	/* whether textValue for all non-null
+														params is populated */
 
 	/*
 	 * params[] may be of length zero if paramFetch is supplied; otherwise it
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index b367838..c96ea32 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -24,6 +24,7 @@
 #include "nodes/plannodes.h"
 #include "storage/procsignal.h"
 #include "utils/guc.h"
+#include "utils/portal.h"
 #include "utils/queryenvironment.h"
 
 
@@ -32,6 +33,8 @@
 
 extern CommandDest whereToSendOutput;
 extern PGDLLIMPORT const char *debug_query_string;
+extern PGDLLIMPORT Portal current_top_portal;
+
 extern int	max_stack_depth;
 extern int	PostAuthDelay;
 
@@ -83,6 +86,7 @@ extern long get_stack_depth_rlimit(void);
 extern void ResetUsage(void);
 extern void ShowUsage(const char *title);
 extern int	check_log_duration(char *msec_str, bool was_logged);
+extern char *get_portal_bind_parameters(Portal portal);
 extern void set_debug_options(int debug_flag,
 				  GucContext context, GucSource source);
 extern bool set_plan_disabling_options(const char *arg,
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index c07e7b9..82e9a04 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -232,6 +232,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
diff --git a/src/include/utils/portal.h b/src/include/utils/portal.h
index bbef89e..d3b2724 100644
--- a/src/include/utils/portal.h
+++ b/src/include/utils/portal.h
@@ -200,7 +200,6 @@ typedef struct PortalData
  */
 #define PortalIsValid(p) PointerIsValid(p)
 
-
 /* Prototypes for functions in utils/mmgr/portalmem.c */
 extern void EnablePortalManager(void);
 extern bool PreCommit_Portals(bool isPrepare);
@@ -215,7 +214,9 @@ extern void AtSubAbort_Portals(SubTransactionId mySubid,
 				   ResourceOwner myXactOwner,
 				   ResourceOwner parentXactOwner);
 extern void AtSubCleanup_Portals(SubTransactionId mySubid);
-extern Portal CreatePortal(const char *name, bool allowDup, bool dupSilent);
+extern Portal CreatePortal(const char *name,
+							bool allowDup,
+							bool dupSilent);
 extern Portal CreateNewPortal(void);
 extern void PinPortal(Portal portal);
 extern void UnpinPortal(Portal portal);
@@ -231,6 +232,7 @@ extern void PortalDefineQuery(Portal portal,
 				  List *stmts,
 				  CachedPlan *cplan);
 extern PlannedStmt *PortalGetPrimaryStmt(Portal portal);
+extern char *GetCurrentPortalBindParameters(Portal portal);
 extern void PortalCreateHoldStore(Portal portal);
 extern void PortalHashTableDeleteAll(void);
 extern bool ThereAreNoReadyPortals(void);

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index f64402a..924a76c 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6270,6 +6270,23 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters" xreflabel="log_parameters">
+      <term><varname>log_parameters</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether the statement is logged with bind parameter values. 
+        It adds some overhead, as postgres will cache textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged. The default is
+        <literal>off</literal>. Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index a98c836..9ee3954 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -404,6 +404,7 @@ EvaluateParams(PreparedStatement *pstmt, List *params,
 	paramLI->parserSetup = NULL;
 	paramLI->parserSetupArg = NULL;
 	paramLI->numParams = num_params;
+	paramLI->hasTextValues = false;
 
 	i = 0;
 	foreach(l, exprstates)
diff --git a/src/backend/executor/functions.c b/src/backend/executor/functions.c
index de41588..195e3c5 100644
--- a/src/backend/executor/functions.c
+++ b/src/backend/executor/functions.c
@@ -921,6 +921,7 @@ postquel_sub_params(SQLFunctionCachePtr fcache,
 			paramLI->parserSetup = NULL;
 			paramLI->parserSetupArg = NULL;
 			paramLI->numParams = nargs;
+			paramLI->hasTextValues = false;
 			fcache->paramLI = paramLI;
 		}
 		else
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 94a53e0..398f0e3 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -2399,6 +2399,7 @@ _SPI_convert_params(int nargs, Oid *argtypes,
 		paramLI->parserSetup = NULL;
 		paramLI->parserSetupArg = NULL;
 		paramLI->numParams = nargs;
+		paramLI->hasTextValues = false;
 
 		for (i = 0; i < nargs; i++)
 		{
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index a89a25e..5aebd428 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -31,6 +31,8 @@
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * We don't copy textual representations here.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -53,6 +55,7 @@ copyParamList(ParamListInfo from)
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
 	retval->numParams = from->numParams;
+	retval->hasTextValues = false;
 
 	for (i = 0; i < from->numParams; i++)
 	{
@@ -229,6 +232,7 @@ RestoreParamList(char **start_address)
 	paramLI->parserSetup = NULL;
 	paramLI->parserSetupArg = NULL;
 	paramLI->numParams = nparams;
+	paramLI->hasTextValues = false;
 
 	for (i = 0; i < nparams; i++)
 	{
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 0c0891b..1f81fba 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -86,6 +86,12 @@
  */
 const char *debug_query_string; /* client-supplied query string */
 
+/*
+ * The top-level portal that the client is immediately working with:
+ * creating, binding, executing, or all at one using simple protocol
+ */
+Portal current_top_portal = NULL;
+
 /* Note: whereToSendOutput is initialized for the bootstrap/standalone case */
 CommandDest whereToSendOutput = DestDebug;
 
@@ -183,7 +189,7 @@ static void forbidden_in_wal_sender(char firstchar);
 static List *pg_rewrite_query(Query *query);
 static bool check_log_statement(List *stmt_list);
 static int	errdetail_execute(List *raw_parsetree_list);
-static int	errdetail_params(ParamListInfo params);
+static int	errdetail_params(Portal portal);
 static int	errdetail_abort(void);
 static int	errdetail_recovery_conflict(void);
 static void start_xact_command(void);
@@ -1694,6 +1700,9 @@ exec_bind_message(StringInfo input_message)
 	else
 		portal = CreatePortal(portal_name, false, false);
 
+	Assert(current_top_portal == NULL);
+	current_top_portal = portal;
+
 	/*
 	 * Prepare to copy stuff into the portal's memory context.  We do all this
 	 * copying first, because it could possibly fail (out-of-memory) and we
@@ -1731,6 +1740,9 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* GUC value can change, so we remember its state to be consistent */
+		bool need_text_values = log_parameters;
+
 		params = (ParamListInfo) palloc(offsetof(ParamListInfoData, params) +
 										numParams * sizeof(ParamExternData));
 		/* we have static list of params, so no hooks needed */
@@ -1741,6 +1753,8 @@ exec_bind_message(StringInfo input_message)
 		params->parserSetup = NULL;
 		params->parserSetupArg = NULL;
 		params->numParams = numParams;
+		/* mark as not having text values before we have populated them all */
+		params->hasTextValues = false;
 
 		for (int paramno = 0; paramno < numParams; paramno++)
 		{
@@ -1807,9 +1821,31 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				if (pstring)
+				{
+					if (need_text_values)
+					{
+						if (pstring == pbuf.data)
+						{
+							/*
+							 * Copy textual representation to portal context.
+							 */
+							params->params[paramno].textValue =
+															pstrdup(pstring);
+						}
+						else
+						{
+							/* Reuse the result of encoding conversion for it */
+							params->params[paramno].textValue = pstring;
+						}
+					}
+					else
+					{
+						/* Free result of encoding conversion */
+						if (pstring != pbuf.data)
+							pfree(pstring);
+					}
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1835,6 +1871,22 @@ exec_bind_message(StringInfo input_message)
 							(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
 							 errmsg("incorrect binary data format in bind parameter %d",
 									paramno + 1)));
+
+				/*
+				 * Compute textual representation for further logging. We waste
+				 * some time and memory here, maybe one day we could skip
+				 * certain types like built-in primitives, which are safe to get
+				 * it calculated later in an aborted xact.
+				 */
+				if (!isNull && need_text_values)
+				{
+					Oid			typoutput;
+					bool		typisvarlena;
+
+					getTypeOutputInfo(ptype, &typoutput, &typisvarlena);
+					params->params[paramno].textValue =
+								OidOutputFunctionCall(typoutput, pval);
+				}
 			}
 			else
 			{
@@ -1859,10 +1911,22 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/*
+		 * now we can safely set it, as we have textValue populated
+		 * for all non-null parameters
+		 */
+		params->hasTextValues = need_text_values;
 	}
 	else
 		params = NULL;
 
+	/*
+	 * Set portal parameters early for them to get logged if an error happens
+	 * on planning stage
+	 */
+	portal->portalParams = params;
+
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
@@ -1936,13 +2000,14 @@ exec_bind_message(StringInfo input_message)
 							*portal_name ? portal_name : "",
 							psrc->query_string),
 					 errhidestmt(true),
-					 errdetail_params(params)));
+					 errdetail_params(portal)));
 			break;
 	}
 
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -1961,7 +2026,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 	char		completionTag[COMPLETION_TAG_BUFSIZE];
 	const char *sourceText;
 	const char *prepStmtName;
-	ParamListInfo portalParams;
 	bool		save_log_statement_stats = log_statement_stats;
 	bool		is_xact_command;
 	bool		execute_is_fetch;
@@ -1978,7 +2042,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 		ereport(ERROR,
 				(errcode(ERRCODE_UNDEFINED_CURSOR),
 				 errmsg("portal \"%s\" does not exist", portal_name)));
-
 	/*
 	 * If the original query was a null string, just return
 	 * EmptyQueryResponse.
@@ -2005,21 +2068,22 @@ exec_execute_message(const char *portal_name, long max_rows)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
-		/*
-		 * An xact command shouldn't have any parameters, which is a good
-		 * thing because they wouldn't be around after finish_xact_command.
-		 */
-		portalParams = NULL;
 	}
 	else
 	{
+		/*
+		 * We do it for non-xact commands only, as an xact command
+		 * 1) shouldn't have any parameters to log;
+		 * 2) may have the portal dropped early.
+		 */
+		Assert(current_top_portal == NULL);
+		current_top_portal = portal;
+
 		sourceText = portal->sourceText;
 		if (portal->prepStmtName)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
-		portalParams = portal->portalParams;
 	}
 
 	/*
@@ -2071,7 +2135,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 						*portal_name ? portal_name : "",
 						sourceText),
 				 errhidestmt(true),
-				 errdetail_params(portalParams)));
+				 errdetail_params(portal)));
 		was_logged = true;
 	}
 
@@ -2160,13 +2224,14 @@ exec_execute_message(const char *portal_name, long max_rows)
 							*portal_name ? portal_name : "",
 							sourceText),
 					 errhidestmt(true),
-					 errdetail_params(portalParams)));
+					 errdetail_params(current_top_portal)));
 			break;
 	}
 
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2304,63 +2369,20 @@ errdetail_execute(List *raw_parsetree_list)
  * Add an errdetail() line showing bind-parameter data, if available.
  */
 static int
-errdetail_params(ParamListInfo params)
+errdetail_params(Portal portal)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
-	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
-
-		pfree(param_str.data);
+	/* Make sure any trash is generated in MessageContext */
+	MemoryContext oldcontext = MemoryContextSwitchTo(MessageContext);
+	char *params_message = get_portal_bind_parameters(portal);
 
-		MemoryContextSwitchTo(oldcontext);
+	if (params_message)
+	{
+		errdetail("parameters: %s", params_message);
+		pfree(params_message);
 	}
 
+	MemoryContextSwitchTo(oldcontext);
+
 	return 0;
 }
 
@@ -2678,6 +2700,94 @@ drop_unnamed_stmt(void)
 	}
 }
 
+/*
+ * get_portal_bind_parameters
+ * 		Get the string containing parameters data, is used for logging.
+ *
+ * Can return NULL if there are no parameters in the portal
+ * or the portal is not valid, or the text representations of the parameters are
+ * not available. If returning a non-NULL value, it allocates memory
+ * for the returned string in the current context, and it's the caller's
+ * responsibility to pfree() it if needed.
+ */
+char *
+get_portal_bind_parameters(Portal portal)
+{
+	ParamListInfo params;
+	StringInfoData param_str;
+
+	/* Fail if no current portal */
+	if (!PortalIsValid(portal))
+		return NULL;
+
+	params = portal->portalParams;
+
+	/* No parameters to format */
+	if (!params || params->numParams == 0)
+		return NULL;
+
+	/*
+	 * We either need textual representation of parameters pre-calcualted,
+	 * or call potentially user-defined I/O functions to convert internal
+	 * representation into text, which cannot be done in an aborted xact
+	 */
+	if (!params->hasTextValues && IsAbortedTransactionBlockState())
+		return NULL;
+
+	initStringInfo(&param_str);
+
+	/* This code doesn't support dynamic param lists */
+	Assert(params->paramFetch == NULL);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *prm = &params->params[paramno];
+		char	   *pstring;
+		char	   *p;
+
+		appendStringInfo(&param_str, "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (prm->isnull)
+		{
+			appendStringInfoString(&param_str, "NULL");
+			continue;
+		}
+
+		if (params->hasTextValues)
+			pstring = prm->textValue;
+		else
+		{
+			Oid			typoutput;
+			bool		typisvarlena;
+
+			if (OidIsValid(prm->ptype))
+			{
+				appendStringInfoString(&param_str, "UNKNOWN TYPE");
+				continue;
+			}
+
+			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
+			pstring = OidOutputFunctionCall(typoutput, prm->value);
+		}
+
+		appendStringInfoCharMacro(&param_str, '\'');
+		for (p = pstring; *p; p++)
+		{
+			if (*p == '\'') /* double single quotes */
+				appendStringInfoCharMacro(&param_str, *p);
+			appendStringInfoCharMacro(&param_str, *p);
+		}
+		appendStringInfoCharMacro(&param_str, '\'');
+
+		if (!params->hasTextValues)
+			pfree(pstring);
+	}
+
+	return param_str.data;
+}
+
 
 /* --------------------------------
  *		signal handler routines used in PostgresMain()
@@ -4031,10 +4141,11 @@ PostgresMain(int argc, char *argv[],
 		EmitErrorReport();
 
 		/*
-		 * Make sure debug_query_string gets reset before we possibly clobber
-		 * the storage it points at.
+		 * Make sure these get reset before we possibly clobber
+		 * the storages they point at.
 		 */
 		debug_query_string = NULL;
+		current_top_portal = NULL;
 
 		/*
 		 * Abort the current transaction in order to recover.
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 8b4720e..6f4ab5a 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -76,6 +76,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 #include "utils/ps_status.h"
 
 
@@ -344,6 +345,7 @@ errstart(int elevel, const char *filename, int lineno,
 		{
 			error_context_stack = NULL;
 			debug_query_string = NULL;
+			current_top_portal = NULL;
 		}
 	}
 	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
@@ -2788,6 +2790,16 @@ write_csvlog(ErrorData *edata)
 	if (print_stmt && edata->cursorpos > 0)
 		appendStringInfo(&buf, "%d", edata->cursorpos);
 	appendStringInfoChar(&buf, ',');
+	if (print_stmt)
+	{
+		char *param_values = get_portal_bind_parameters(current_top_portal);
+		if (param_values != NULL)
+		{
+			appendCSVLiteral(&buf, param_values);
+			pfree(param_values);
+		}
+	}
+	appendStringInfoChar(&buf, ',');
 
 	/* file error location */
 	if (Log_error_verbosity >= PGERROR_VERBOSE)
@@ -2944,6 +2956,17 @@ send_message_to_server_log(ErrorData *edata)
 		appendStringInfoString(&buf, _("STATEMENT:  "));
 		append_with_tabs(&buf, debug_query_string);
 		appendStringInfoChar(&buf, '\n');
+
+		if (log_parameters)
+		{
+			char *param_values = get_portal_bind_parameters(current_top_portal);
+			if (param_values != NULL)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("PARAMETERS:  %s\n"), param_values);
+				pfree(param_values);
+			}
+		}
 	}
 
 #ifdef HAVE_SYSLOG
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 7eda7fd..f072741 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -464,6 +464,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1235,6 +1236,15 @@ static struct config_bool ConfigureNamesBool[] =
 		NULL, NULL, NULL
 	},
 	{
+		{"log_parameters", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters,
+		false,
+		NULL, NULL, NULL
+	},
+	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
 			NULL
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index f7c1dee..6d8bdc0 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -526,6 +526,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters = off			# log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index ded3b3a..3b850a4 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -93,6 +93,7 @@ typedef struct ParamExternData
 	bool		isnull;			/* is it NULL? */
 	uint16		pflags;			/* flag bits, see above */
 	Oid			ptype;			/* parameter's datatype, or 0 */
+	char	   *textValue;		/* textual representation for debug purposes */
 } ParamExternData;
 
 typedef struct ParamListInfoData *ParamListInfo;
@@ -116,6 +117,8 @@ typedef struct ParamListInfoData
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
 	int			numParams;		/* nominal/maximum # of Params represented */
+	bool		hasTextValues;	/* whether textValue for all non-null
+														params is populated */
 
 	/*
 	 * params[] may be of length zero if paramFetch is supplied; otherwise it
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index b367838..c96ea32 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -24,6 +24,7 @@
 #include "nodes/plannodes.h"
 #include "storage/procsignal.h"
 #include "utils/guc.h"
+#include "utils/portal.h"
 #include "utils/queryenvironment.h"
 
 
@@ -32,6 +33,8 @@
 
 extern CommandDest whereToSendOutput;
 extern PGDLLIMPORT const char *debug_query_string;
+extern PGDLLIMPORT Portal current_top_portal;
+
 extern int	max_stack_depth;
 extern int	PostAuthDelay;
 
@@ -83,6 +86,7 @@ extern long get_stack_depth_rlimit(void);
 extern void ResetUsage(void);
 extern void ShowUsage(const char *title);
 extern int	check_log_duration(char *msec_str, bool was_logged);
+extern char *get_portal_bind_parameters(Portal portal);
 extern void set_debug_options(int debug_flag,
 				  GucContext context, GucSource source);
 extern bool set_plan_disabling_options(const char *arg,
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index c07e7b9..82e9a04 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -232,6 +232,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index b6f5822..997e6e8 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6274,6 +6274,23 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether the statement is logged with bind parameter values. 
+        It adds some overhead, as postgres will cache textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged. The default is
+        <literal>off</literal>. Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index a98c836..9ee3954 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -404,6 +404,7 @@ EvaluateParams(PreparedStatement *pstmt, List *params,
 	paramLI->parserSetup = NULL;
 	paramLI->parserSetupArg = NULL;
 	paramLI->numParams = num_params;
+	paramLI->hasTextValues = false;
 
 	i = 0;
 	foreach(l, exprstates)
diff --git a/src/backend/executor/functions.c b/src/backend/executor/functions.c
index c6b7203..e107fa3 100644
--- a/src/backend/executor/functions.c
+++ b/src/backend/executor/functions.c
@@ -921,6 +921,7 @@ postquel_sub_params(SQLFunctionCachePtr fcache,
 			paramLI->parserSetup = NULL;
 			paramLI->parserSetupArg = NULL;
 			paramLI->numParams = nargs;
+			paramLI->hasTextValues = false;
 			fcache->paramLI = paramLI;
 		}
 		else
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 94a53e0..398f0e3 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -2399,6 +2399,7 @@ _SPI_convert_params(int nargs, Oid *argtypes,
 		paramLI->parserSetup = NULL;
 		paramLI->parserSetupArg = NULL;
 		paramLI->numParams = nargs;
+		paramLI->hasTextValues = false;
 
 		for (i = 0; i < nargs; i++)
 		{
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index a89a25e..5aebd428 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -31,6 +31,8 @@
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * We don't copy textual representations here.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -53,6 +55,7 @@ copyParamList(ParamListInfo from)
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
 	retval->numParams = from->numParams;
+	retval->hasTextValues = false;
 
 	for (i = 0; i < from->numParams; i++)
 	{
@@ -229,6 +232,7 @@ RestoreParamList(char **start_address)
 	paramLI->parserSetup = NULL;
 	paramLI->parserSetupArg = NULL;
 	paramLI->numParams = nparams;
+	paramLI->hasTextValues = false;
 
 	for (i = 0; i < nparams; i++)
 	{
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index e773f20..69fa610 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -86,6 +86,12 @@
  */
 const char *debug_query_string; /* client-supplied query string */
 
+/*
+ * The top-level portal that the client is immediately working with:
+ * creating, binding, executing, or all at one using simple protocol
+ */
+Portal current_top_portal = NULL;
+
 /* Note: whereToSendOutput is initialized for the bootstrap/standalone case */
 CommandDest whereToSendOutput = DestDebug;
 
@@ -1694,6 +1700,9 @@ exec_bind_message(StringInfo input_message)
 	else
 		portal = CreatePortal(portal_name, false, false);
 
+	Assert(current_top_portal == NULL);
+	current_top_portal = portal;
+
 	/*
 	 * Prepare to copy stuff into the portal's memory context.  We do all this
 	 * copying first, because it could possibly fail (out-of-memory) and we
@@ -1731,6 +1740,9 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* GUC value can change, so we remember its state to be consistent */
+		bool need_text_values = log_parameters_on_error;
+
 		params = (ParamListInfo) palloc(offsetof(ParamListInfoData, params) +
 										numParams * sizeof(ParamExternData));
 		/* we have static list of params, so no hooks needed */
@@ -1741,6 +1753,8 @@ exec_bind_message(StringInfo input_message)
 		params->parserSetup = NULL;
 		params->parserSetupArg = NULL;
 		params->numParams = numParams;
+		/* mark as not having text values before we have populated them all */
+		params->hasTextValues = false;
 
 		for (int paramno = 0; paramno < numParams; paramno++)
 		{
@@ -1807,9 +1821,31 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				if (pstring)
+				{
+					if (need_text_values)
+					{
+						if (pstring == pbuf.data)
+						{
+							/*
+							 * Copy textual representation to portal context.
+							 */
+							params->params[paramno].textValue =
+															pstrdup(pstring);
+						}
+						else
+						{
+							/* Reuse the result of encoding conversion for it */
+							params->params[paramno].textValue = pstring;
+						}
+					}
+					else
+					{
+						/* Free result of encoding conversion */
+						if (pstring != pbuf.data)
+							pfree(pstring);
+					}
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1835,6 +1871,22 @@ exec_bind_message(StringInfo input_message)
 							(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
 							 errmsg("incorrect binary data format in bind parameter %d",
 									paramno + 1)));
+
+				/*
+				 * Compute textual representation for further logging. We waste
+				 * some time and memory here, maybe one day we could skip
+				 * certain types like built-in primitives, which are safe to get
+				 * it calculated later in an aborted xact.
+				 */
+				if (!isNull && need_text_values)
+				{
+					Oid			typoutput;
+					bool		typisvarlena;
+
+					getTypeOutputInfo(ptype, &typoutput, &typisvarlena);
+					params->params[paramno].textValue =
+								OidOutputFunctionCall(typoutput, pval);
+				}
 			}
 			else
 			{
@@ -1859,10 +1911,22 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/*
+		 * now we can safely set it, as we have textValue populated
+		 * for all non-null parameters
+		 */
+		params->hasTextValues = need_text_values;
 	}
 	else
 		params = NULL;
 
+	/*
+	 * Set portal parameters early for them to get logged if an error happens
+	 * on planning stage
+	 */
+	portal->portalParams = params;
+
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
@@ -1943,6 +2007,7 @@ exec_bind_message(StringInfo input_message)
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -1978,7 +2043,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 		ereport(ERROR,
 				(errcode(ERRCODE_UNDEFINED_CURSOR),
 				 errmsg("portal \"%s\" does not exist", portal_name)));
-
 	/*
 	 * If the original query was a null string, just return
 	 * EmptyQueryResponse.
@@ -2000,26 +2064,30 @@ exec_execute_message(const char *portal_name, long max_rows)
 	 */
 	if (is_xact_command)
 	{
+		portalParams = portal->portalParams;
+
 		sourceText = pstrdup(portal->sourceText);
 		if (portal->prepStmtName)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
-		/*
-		 * An xact command shouldn't have any parameters, which is a good
-		 * thing because they wouldn't be around after finish_xact_command.
-		 */
-		portalParams = NULL;
 	}
 	else
 	{
+		/*
+		 * We do it for non-xact commands only, as an xact command
+		 * 1) shouldn't have any parameters to log;
+		 * 2) may have the portal dropped early.
+		 */
+		Assert(current_top_portal == NULL);
+		current_top_portal = portal;
+		portalParams = NULL;
+
 		sourceText = portal->sourceText;
 		if (portal->prepStmtName)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
-		portalParams = portal->portalParams;
 	}
 
 	/*
@@ -2160,13 +2228,14 @@ exec_execute_message(const char *portal_name, long max_rows)
 							*portal_name ? portal_name : "",
 							sourceText),
 					 errhidestmt(true),
-					 errdetail_params(portalParams)));
+					 errdetail_params(current_top_portal->portalParams)));
 			break;
 	}
 
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2306,61 +2375,18 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
-	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
+	/* Make sure any trash is generated in MessageContext */
+	MemoryContext oldcontext = MemoryContextSwitchTo(MessageContext);
+	char *params_message = get_portal_bind_parameters(params);
 
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
-
-		pfree(param_str.data);
-
-		MemoryContextSwitchTo(oldcontext);
+	if (params_message)
+	{
+		errdetail("parameters: %s", params_message);
+		pfree(params_message);
 	}
 
+	MemoryContextSwitchTo(oldcontext);
+
 	return 0;
 }
 
@@ -2678,6 +2704,89 @@ drop_unnamed_stmt(void)
 	}
 }
 
+/*
+ * get_portal_bind_parameters
+ * 		Get the string containing parameters data, is used for logging.
+ *
+ * Can return NULL if there are no parameters in the portal
+ * or the portal is not valid, or the text representations of the parameters are
+ * not available. If returning a non-NULL value, it allocates memory
+ * for the returned string in the current context, and it's the caller's
+ * responsibility to pfree() it if needed.
+ */
+char *
+get_portal_bind_parameters(ParamListInfo params)
+{
+	StringInfoData param_str;
+
+	/* No parameters to format */
+	if (!params || params->numParams == 0)
+		return NULL;
+
+			elog(WARNING, "params->hasTextValues=%d, IsAbortedTransactionBlockState()=%d",
+				           params->hasTextValues && IsAbortedTransactionBlockState());
+	/*
+	 * We either need textual representation of parameters pre-calcualted,
+	 * or call potentially user-defined I/O functions to convert internal
+	 * representation into text, which cannot be done in an aborted xact
+	 */
+	if (!params->hasTextValues && IsAbortedTransactionBlockState())
+		return NULL;
+
+	initStringInfo(&param_str);
+
+	/* This code doesn't support dynamic param lists */
+	Assert(params->paramFetch == NULL);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *prm = &params->params[paramno];
+		char	   *pstring;
+		char	   *p;
+
+		appendStringInfo(&param_str, "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (prm->isnull)
+		{
+			appendStringInfoString(&param_str, "NULL");
+			continue;
+		}
+
+		if (params->hasTextValues)
+			pstring = prm->textValue;
+		else
+		{
+			Oid			typoutput;
+			bool		typisvarlena;
+
+			if (!OidIsValid(prm->ptype))
+			{
+				appendStringInfoString(&param_str, "UNKNOWN TYPE");
+				continue;
+			}
+
+			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
+			pstring = OidOutputFunctionCall(typoutput, prm->value);
+		}
+
+		appendStringInfoCharMacro(&param_str, '\'');
+		for (p = pstring; *p; p++)
+		{
+			if (*p == '\'') /* double single quotes */
+				appendStringInfoCharMacro(&param_str, *p);
+			appendStringInfoCharMacro(&param_str, *p);
+		}
+		appendStringInfoCharMacro(&param_str, '\'');
+
+		if (!params->hasTextValues)
+			pfree(pstring);
+	}
+
+	return param_str.data;
+}
+
 
 /* --------------------------------
  *		signal handler routines used in PostgresMain()
@@ -4031,10 +4140,11 @@ PostgresMain(int argc, char *argv[],
 		EmitErrorReport();
 
 		/*
-		 * Make sure debug_query_string gets reset before we possibly clobber
-		 * the storage it points at.
+		 * Make sure these get reset before we possibly clobber
+		 * the storages they point at.
 		 */
 		debug_query_string = NULL;
+		current_top_portal = NULL;
 
 		/*
 		 * Abort the current transaction in order to recover.
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 8b4720e..e18d9e5 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -76,6 +76,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 #include "utils/ps_status.h"
 
 
@@ -344,6 +345,7 @@ errstart(int elevel, const char *filename, int lineno,
 		{
 			error_context_stack = NULL;
 			debug_query_string = NULL;
+			current_top_portal = NULL;
 		}
 	}
 	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
@@ -2788,6 +2790,18 @@ write_csvlog(ErrorData *edata)
 	if (print_stmt && edata->cursorpos > 0)
 		appendStringInfo(&buf, "%d", edata->cursorpos);
 	appendStringInfoChar(&buf, ',');
+	if (print_stmt && log_parameters_on_error
+					&& PortalIsValid(current_top_portal))
+	{
+		char *param_values =
+			get_portal_bind_parameters(current_top_portal->portalParams);
+		if (param_values != NULL)
+		{
+			appendCSVLiteral(&buf, param_values);
+			pfree(param_values);
+		}
+	}
+	appendStringInfoChar(&buf, ',');
 
 	/* file error location */
 	if (Log_error_verbosity >= PGERROR_VERBOSE)
@@ -2944,6 +2958,18 @@ send_message_to_server_log(ErrorData *edata)
 		appendStringInfoString(&buf, _("STATEMENT:  "));
 		append_with_tabs(&buf, debug_query_string);
 		appendStringInfoChar(&buf, '\n');
+
+		if (log_parameters_on_error && PortalIsValid(current_top_portal))
+		{
+			char *param_values =
+				get_portal_bind_parameters(current_top_portal->portalParams);
+			if (param_values != NULL)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("PARAMETERS:  %s\n"), param_values);
+				pfree(param_values);
+			}
+		}
 	}
 
 #ifdef HAVE_SYSLOG
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index c216ed0..892ca77 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -465,6 +465,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1242,6 +1243,15 @@ static struct config_bool ConfigureNamesBool[] =
 		NULL, NULL, NULL
 	},
 	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
+	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
 			NULL
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index a21865a..b2865d8 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -526,6 +526,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index ded3b3a..3b850a4 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -93,6 +93,7 @@ typedef struct ParamExternData
 	bool		isnull;			/* is it NULL? */
 	uint16		pflags;			/* flag bits, see above */
 	Oid			ptype;			/* parameter's datatype, or 0 */
+	char	   *textValue;		/* textual representation for debug purposes */
 } ParamExternData;
 
 typedef struct ParamListInfoData *ParamListInfo;
@@ -116,6 +117,8 @@ typedef struct ParamListInfoData
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
 	int			numParams;		/* nominal/maximum # of Params represented */
+	bool		hasTextValues;	/* whether textValue for all non-null
+														params is populated */
 
 	/*
 	 * params[] may be of length zero if paramFetch is supplied; otherwise it
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index b367838..2cfa2ac 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -24,6 +24,7 @@
 #include "nodes/plannodes.h"
 #include "storage/procsignal.h"
 #include "utils/guc.h"
+#include "utils/portal.h"
 #include "utils/queryenvironment.h"
 
 
@@ -32,6 +33,8 @@
 
 extern CommandDest whereToSendOutput;
 extern PGDLLIMPORT const char *debug_query_string;
+extern PGDLLIMPORT Portal current_top_portal;
+
 extern int	max_stack_depth;
 extern int	PostAuthDelay;
 
@@ -83,6 +86,7 @@ extern long get_stack_depth_rlimit(void);
 extern void ResetUsage(void);
 extern void ShowUsage(const char *title);
 extern int	check_log_duration(char *msec_str, bool was_logged);
+extern char *get_portal_bind_parameters(ParamListInfo params);
 extern void set_debug_options(int debug_flag,
 				  GucContext context, GucSource source);
 extern bool set_plan_disabling_options(const char *arg,
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index c07e7b9..1034fc2 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -232,6 +232,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 8bd57f3..59638f8 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6312,6 +6312,23 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether the statement is logged with bind parameter values. 
+        It adds some overhead, as postgres will cache textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged. The default is
+        <literal>off</literal>. Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index a98c836..9ee3954 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -404,6 +404,7 @@ EvaluateParams(PreparedStatement *pstmt, List *params,
 	paramLI->parserSetup = NULL;
 	paramLI->parserSetupArg = NULL;
 	paramLI->numParams = num_params;
+	paramLI->hasTextValues = false;
 
 	i = 0;
 	foreach(l, exprstates)
diff --git a/src/backend/executor/functions.c b/src/backend/executor/functions.c
index c6b7203..e107fa3 100644
--- a/src/backend/executor/functions.c
+++ b/src/backend/executor/functions.c
@@ -921,6 +921,7 @@ postquel_sub_params(SQLFunctionCachePtr fcache,
 			paramLI->parserSetup = NULL;
 			paramLI->parserSetupArg = NULL;
 			paramLI->numParams = nargs;
+			paramLI->hasTextValues = false;
 			fcache->paramLI = paramLI;
 		}
 		else
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 70c03e0..019cef7 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -2399,6 +2399,7 @@ _SPI_convert_params(int nargs, Oid *argtypes,
 		paramLI->parserSetup = NULL;
 		paramLI->parserSetupArg = NULL;
 		paramLI->numParams = nargs;
+		paramLI->hasTextValues = false;
 
 		for (i = 0; i < nargs; i++)
 		{
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index a89a25e..72d7dd1 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -31,6 +31,10 @@
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * Since this function is never used for copying parameters into a top portal,
+ * we don't copy textual representations. Neither we set the hasTextValues
+ * flag, so noone will access them.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -53,6 +57,7 @@ copyParamList(ParamListInfo from)
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
 	retval->numParams = from->numParams;
+	retval->hasTextValues = false;
 
 	for (i = 0; i < from->numParams; i++)
 	{
@@ -229,6 +234,7 @@ RestoreParamList(char **start_address)
 	paramLI->parserSetup = NULL;
 	paramLI->parserSetupArg = NULL;
 	paramLI->numParams = nparams;
+	paramLI->hasTextValues = false;
 
 	for (i = 0; i < nparams; i++)
 	{
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 8b4d94c..38df7ca 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -86,6 +86,12 @@
  */
 const char *debug_query_string; /* client-supplied query string */
 
+/*
+ * The top-level portal that the client is immediately working with:
+ * creating, binding, executing, or all at one using simple protocol
+ */
+Portal current_top_portal = NULL;
+
 /* Note: whereToSendOutput is initialized for the bootstrap/standalone case */
 CommandDest whereToSendOutput = DestDebug;
 
@@ -1694,6 +1700,9 @@ exec_bind_message(StringInfo input_message)
 	else
 		portal = CreatePortal(portal_name, false, false);
 
+	Assert(current_top_portal == NULL);
+	current_top_portal = portal;
+
 	/*
 	 * Prepare to copy stuff into the portal's memory context.  We do all this
 	 * copying first, because it could possibly fail (out-of-memory) and we
@@ -1731,6 +1740,9 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* GUC value can change, so we remember its state to be consistent */
+		bool need_text_values = log_parameters_on_error;
+
 		params = (ParamListInfo) palloc(offsetof(ParamListInfoData, params) +
 										numParams * sizeof(ParamExternData));
 		/* we have static list of params, so no hooks needed */
@@ -1741,6 +1753,8 @@ exec_bind_message(StringInfo input_message)
 		params->parserSetup = NULL;
 		params->parserSetupArg = NULL;
 		params->numParams = numParams;
+		/* mark as not having text values before we have populated them all */
+		params->hasTextValues = false;
 
 		for (int paramno = 0; paramno < numParams; paramno++)
 		{
@@ -1807,9 +1821,31 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				if (pstring)
+				{
+					if (need_text_values)
+					{
+						if (pstring == pbuf.data)
+						{
+							/*
+							 * Copy textual representation to portal context.
+							 */
+							params->params[paramno].textValue =
+															pstrdup(pstring);
+						}
+						else
+						{
+							/* Reuse the result of encoding conversion for it */
+							params->params[paramno].textValue = pstring;
+						}
+					}
+					else
+					{
+						/* Free result of encoding conversion */
+						if (pstring != pbuf.data)
+							pfree(pstring);
+					}
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1835,6 +1871,22 @@ exec_bind_message(StringInfo input_message)
 							(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
 							 errmsg("incorrect binary data format in bind parameter %d",
 									paramno + 1)));
+
+				/*
+				 * Compute textual representation for further logging. We waste
+				 * some time and memory here, maybe one day we could skip
+				 * certain types like built-in primitives, which are safe to get
+				 * it calculated later in an aborted xact.
+				 */
+				if (!isNull && need_text_values)
+				{
+					Oid			typoutput;
+					bool		typisvarlena;
+
+					getTypeOutputInfo(ptype, &typoutput, &typisvarlena);
+					params->params[paramno].textValue =
+								OidOutputFunctionCall(typoutput, pval);
+				}
 			}
 			else
 			{
@@ -1859,10 +1911,22 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/*
+		 * now we can safely set it, as we have textValue populated
+		 * for all non-null parameters
+		 */
+		params->hasTextValues = need_text_values;
 	}
 	else
 		params = NULL;
 
+	/*
+	 * Set portal parameters early for them to get logged if an error happens
+	 * on planning stage
+	 */
+	portal->portalParams = params;
+
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
@@ -1943,6 +2007,7 @@ exec_bind_message(StringInfo input_message)
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -1978,7 +2043,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 		ereport(ERROR,
 				(errcode(ERRCODE_UNDEFINED_CURSOR),
 				 errmsg("portal \"%s\" does not exist", portal_name)));
-
 	/*
 	 * If the original query was a null string, just return
 	 * EmptyQueryResponse.
@@ -1993,32 +2057,49 @@ exec_execute_message(const char *portal_name, long max_rows)
 	/* Does the portal contain a transaction command? */
 	is_xact_command = IsTransactionStmtList(portal->stmts);
 
-	/*
-	 * We must copy the sourceText and prepStmtName into MessageContext in
-	 * case the portal is destroyed during finish_xact_command. Can avoid the
-	 * copy if it's not an xact command, though.
-	 */
 	if (is_xact_command)
 	{
+		/*
+		 * We must copy the sourceText and prepStmtName into MessageContext in
+		 * case the portal is destroyed during finish_xact_command.
+		 */
 		sourceText = pstrdup(portal->sourceText);
 		if (portal->prepStmtName)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
 		/*
 		 * An xact command shouldn't have any parameters, which is a good
 		 * thing because they wouldn't be around after finish_xact_command.
 		 */
 		portalParams = NULL;
+
+		/*
+		 * We don't set current top portal for xact cmds, as
+		 * 1) the portal may be destroyed earlier than the error happens
+		 * 2) it anyway has no parameters in it to log
+		 */
+		Assert(current_top_portal == NULL);
 	}
 	else
 	{
+		/*
+		 * The portal will remain there until we leave the function, so it's
+		 * safe avoid copying and just to refer to the data in its memory
+		 * context instead
+		 */
 		sourceText = portal->sourceText;
 		if (portal->prepStmtName)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
+
+		/*
+		 * For non-xact commands, we remember the current portal and its bind
+		 * parameters for further use in logging
+		 */
+		Assert(current_top_portal == NULL);
+		current_top_portal = portal;
 		portalParams = portal->portalParams;
 	}
 
@@ -2167,6 +2248,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2306,61 +2388,18 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
-	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
+	/* Make sure any trash is generated in MessageContext */
+	MemoryContext oldcontext = MemoryContextSwitchTo(MessageContext);
+	char *params_message = get_portal_bind_parameters(params);
 
-		pfree(param_str.data);
-
-		MemoryContextSwitchTo(oldcontext);
+	if (params_message)
+	{
+		errdetail("parameters: %s", params_message);
+		pfree(params_message);
 	}
 
+	MemoryContextSwitchTo(oldcontext);
+
 	return 0;
 }
 
@@ -2678,6 +2717,87 @@ drop_unnamed_stmt(void)
 	}
 }
 
+/*
+ * get_portal_bind_parameters
+ * 		Get the string containing parameters data, is used for logging.
+ *
+ * Can return NULL if there are no parameters in the portal
+ * or the portal is not valid, or the text representations of the parameters are
+ * not available. If returning a non-NULL value, it allocates memory
+ * for the returned string in the current context, and it's the caller's
+ * responsibility to pfree() it if needed.
+ */
+char *
+get_portal_bind_parameters(ParamListInfo params)
+{
+	StringInfoData param_str;
+
+	/* No parameters to format */
+	if (!params || params->numParams == 0)
+		return NULL;
+
+	/*
+	 * We either need textual representation of parameters pre-calcualted,
+	 * or call potentially user-defined I/O functions to convert internal
+	 * representation into text, which cannot be done in an aborted xact
+	 */
+	if (!params->hasTextValues && IsAbortedTransactionBlockState())
+		return NULL;
+
+	initStringInfo(&param_str);
+
+	/* This code doesn't support dynamic param lists */
+	Assert(params->paramFetch == NULL);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *prm = &params->params[paramno];
+		char	   *pstring;
+		char	   *p;
+
+		appendStringInfo(&param_str, "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (prm->isnull)
+		{
+			appendStringInfoString(&param_str, "NULL");
+			continue;
+		}
+
+		if (params->hasTextValues)
+			pstring = prm->textValue;
+		else
+		{
+			Oid			typoutput;
+			bool		typisvarlena;
+
+			if (!OidIsValid(prm->ptype))
+			{
+				appendStringInfoString(&param_str, "UNKNOWN TYPE");
+				continue;
+			}
+
+			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
+			pstring = OidOutputFunctionCall(typoutput, prm->value);
+		}
+
+		appendStringInfoCharMacro(&param_str, '\'');
+		for (p = pstring; *p; p++)
+		{
+			if (*p == '\'') /* double single quotes */
+				appendStringInfoCharMacro(&param_str, *p);
+			appendStringInfoCharMacro(&param_str, *p);
+		}
+		appendStringInfoCharMacro(&param_str, '\'');
+
+		if (!params->hasTextValues)
+			pfree(pstring);
+	}
+
+	return param_str.data;
+}
+
 
 /* --------------------------------
  *		signal handler routines used in PostgresMain()
@@ -4031,10 +4151,11 @@ PostgresMain(int argc, char *argv[],
 		EmitErrorReport();
 
 		/*
-		 * Make sure debug_query_string gets reset before we possibly clobber
-		 * the storage it points at.
+		 * Make sure these get reset before we possibly clobber
+		 * the storages they point at.
 		 */
 		debug_query_string = NULL;
+		current_top_portal = NULL;
 
 		/*
 		 * Abort the current transaction in order to recover.
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 8b4720e..e18d9e5 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -76,6 +76,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 #include "utils/ps_status.h"
 
 
@@ -344,6 +345,7 @@ errstart(int elevel, const char *filename, int lineno,
 		{
 			error_context_stack = NULL;
 			debug_query_string = NULL;
+			current_top_portal = NULL;
 		}
 	}
 	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
@@ -2788,6 +2790,18 @@ write_csvlog(ErrorData *edata)
 	if (print_stmt && edata->cursorpos > 0)
 		appendStringInfo(&buf, "%d", edata->cursorpos);
 	appendStringInfoChar(&buf, ',');
+	if (print_stmt && log_parameters_on_error
+					&& PortalIsValid(current_top_portal))
+	{
+		char *param_values =
+			get_portal_bind_parameters(current_top_portal->portalParams);
+		if (param_values != NULL)
+		{
+			appendCSVLiteral(&buf, param_values);
+			pfree(param_values);
+		}
+	}
+	appendStringInfoChar(&buf, ',');
 
 	/* file error location */
 	if (Log_error_verbosity >= PGERROR_VERBOSE)
@@ -2944,6 +2958,18 @@ send_message_to_server_log(ErrorData *edata)
 		appendStringInfoString(&buf, _("STATEMENT:  "));
 		append_with_tabs(&buf, debug_query_string);
 		appendStringInfoChar(&buf, '\n');
+
+		if (log_parameters_on_error && PortalIsValid(current_top_portal))
+		{
+			char *param_values =
+				get_portal_bind_parameters(current_top_portal->portalParams);
+			if (param_values != NULL)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("PARAMETERS:  %s\n"), param_values);
+				pfree(param_values);
+			}
+		}
 	}
 
 #ifdef HAVE_SYSLOG
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 156d147..a83fe3c 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -480,6 +480,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1257,6 +1258,15 @@ static struct config_bool ConfigureNamesBool[] =
 		NULL, NULL, NULL
 	},
 	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
+	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
 			NULL
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 194f312..e8f74a2 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -528,6 +528,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index ded3b3a..3b850a4 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -93,6 +93,7 @@ typedef struct ParamExternData
 	bool		isnull;			/* is it NULL? */
 	uint16		pflags;			/* flag bits, see above */
 	Oid			ptype;			/* parameter's datatype, or 0 */
+	char	   *textValue;		/* textual representation for debug purposes */
 } ParamExternData;
 
 typedef struct ParamListInfoData *ParamListInfo;
@@ -116,6 +117,8 @@ typedef struct ParamListInfoData
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
 	int			numParams;		/* nominal/maximum # of Params represented */
+	bool		hasTextValues;	/* whether textValue for all non-null
+														params is populated */
 
 	/*
 	 * params[] may be of length zero if paramFetch is supplied; otherwise it
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index b367838..2cfa2ac 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -24,6 +24,7 @@
 #include "nodes/plannodes.h"
 #include "storage/procsignal.h"
 #include "utils/guc.h"
+#include "utils/portal.h"
 #include "utils/queryenvironment.h"
 
 
@@ -32,6 +33,8 @@
 
 extern CommandDest whereToSendOutput;
 extern PGDLLIMPORT const char *debug_query_string;
+extern PGDLLIMPORT Portal current_top_portal;
+
 extern int	max_stack_depth;
 extern int	PostAuthDelay;
 
@@ -83,6 +86,7 @@ extern long get_stack_depth_rlimit(void);
 extern void ResetUsage(void);
 extern void ShowUsage(const char *title);
 extern int	check_log_duration(char *msec_str, bool was_logged);
+extern char *get_portal_bind_parameters(ParamListInfo params);
 extern void set_debug_options(int debug_flag,
 				  GucContext context, GucSource source);
 extern bool set_plan_disabling_options(const char *arg,
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index c07e7b9..1034fc2 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -232,6 +232,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index d383de2..1442f30 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6330,6 +6330,23 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether the statement is logged with bind parameter values. 
+        It adds some overhead, as postgres will cache textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged. The default is
+        <literal>off</literal>. Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index f5d5613..5e5ccf1 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -45,6 +45,7 @@ makeParamList(int numParams)
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
 	retval->numParams = numParams;
+	retval->hasTextValues = false;
 
 	return retval;
 }
@@ -58,6 +59,10 @@ makeParamList(int numParams)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * Since this function is never used for copying parameters into a top portal,
+ * we don't copy textual representations. Neither we set the hasTextValues
+ * flag, so noone will access them.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index f9ce3d8..e097ce8 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -86,6 +86,12 @@
  */
 const char *debug_query_string; /* client-supplied query string */
 
+/*
+ * The top-level portal that the client is immediately working with:
+ * creating, binding, executing, or all at one using simple protocol
+ */
+Portal current_top_portal = NULL;
+
 /* Note: whereToSendOutput is initialized for the bootstrap/standalone case */
 CommandDest whereToSendOutput = DestDebug;
 
@@ -1694,6 +1700,9 @@ exec_bind_message(StringInfo input_message)
 	else
 		portal = CreatePortal(portal_name, false, false);
 
+	Assert(current_top_portal == NULL);
+	current_top_portal = portal;
+
 	/*
 	 * Prepare to copy stuff into the portal's memory context.  We do all this
 	 * copying first, because it could possibly fail (out-of-memory) and we
@@ -1731,6 +1740,9 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* GUC value can change, so we remember its state to be consistent */
+		bool need_text_values = log_parameters_on_error;
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1798,9 +1810,31 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				if (pstring)
+				{
+					if (need_text_values)
+					{
+						if (pstring == pbuf.data)
+						{
+							/*
+							 * Copy textual representation to portal context.
+							 */
+							params->params[paramno].textValue =
+															pstrdup(pstring);
+						}
+						else
+						{
+							/* Reuse the result of encoding conversion for it */
+							params->params[paramno].textValue = pstring;
+						}
+					}
+					else
+					{
+						/* Free result of encoding conversion */
+						if (pstring != pbuf.data)
+							pfree(pstring);
+					}
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1826,6 +1860,22 @@ exec_bind_message(StringInfo input_message)
 							(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
 							 errmsg("incorrect binary data format in bind parameter %d",
 									paramno + 1)));
+
+				/*
+				 * Compute textual representation for further logging. We waste
+				 * some time and memory here, maybe one day we could skip
+				 * certain types like built-in primitives, which are safe to get
+				 * it calculated later in an aborted xact.
+				 */
+				if (!isNull && need_text_values)
+				{
+					Oid			typoutput;
+					bool		typisvarlena;
+
+					getTypeOutputInfo(ptype, &typoutput, &typisvarlena);
+					params->params[paramno].textValue =
+								OidOutputFunctionCall(typoutput, pval);
+				}
 			}
 			else
 			{
@@ -1850,10 +1900,22 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/*
+		 * only now we can safely set it, as we have textValue populated
+		 * for all non-null parameters
+		 */
+		params->hasTextValues = need_text_values;
 	}
 	else
 		params = NULL;
 
+	/*
+	 * Set portal parameters early for them to get logged if an error happens
+	 * on planning stage
+	 */
+	portal->portalParams = params;
+
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
@@ -1934,6 +1996,7 @@ exec_bind_message(StringInfo input_message)
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -1969,7 +2032,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 		ereport(ERROR,
 				(errcode(ERRCODE_UNDEFINED_CURSOR),
 				 errmsg("portal \"%s\" does not exist", portal_name)));
-
 	/*
 	 * If the original query was a null string, just return
 	 * EmptyQueryResponse.
@@ -1984,32 +2046,49 @@ exec_execute_message(const char *portal_name, long max_rows)
 	/* Does the portal contain a transaction command? */
 	is_xact_command = IsTransactionStmtList(portal->stmts);
 
-	/*
-	 * We must copy the sourceText and prepStmtName into MessageContext in
-	 * case the portal is destroyed during finish_xact_command. Can avoid the
-	 * copy if it's not an xact command, though.
-	 */
 	if (is_xact_command)
 	{
+		/*
+		 * We must copy the sourceText and prepStmtName into MessageContext in
+		 * case the portal is destroyed during finish_xact_command.
+		 */
 		sourceText = pstrdup(portal->sourceText);
 		if (portal->prepStmtName)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
 		/*
 		 * An xact command shouldn't have any parameters, which is a good
 		 * thing because they wouldn't be around after finish_xact_command.
 		 */
 		portalParams = NULL;
+
+		/*
+		 * We don't set current top portal for xact cmds, as
+		 * 1) the portal may be destroyed earlier than the error happens
+		 * 2) it anyway has no parameters in it to log
+		 */
+		Assert(current_top_portal == NULL);
 	}
 	else
 	{
+		/*
+		 * The portal will remain there until we leave the function, so it's
+		 * safe avoid copying and just to refer to the data in its memory
+		 * context instead
+		 */
 		sourceText = portal->sourceText;
 		if (portal->prepStmtName)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
+
+		/*
+		 * For non-xact commands, we remember the current portal and its bind
+		 * parameters for further use in logging
+		 */
+		Assert(current_top_portal == NULL);
+		current_top_portal = portal;
 		portalParams = portal->portalParams;
 	}
 
@@ -2158,6 +2237,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2297,61 +2377,18 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
-	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
+	/* Make sure any trash is generated in MessageContext */
+	MemoryContext oldcontext = MemoryContextSwitchTo(MessageContext);
+	char *params_message = get_portal_bind_parameters(params);
 
-		pfree(param_str.data);
-
-		MemoryContextSwitchTo(oldcontext);
+	if (params_message)
+	{
+		errdetail("parameters: %s", params_message);
+		pfree(params_message);
 	}
 
+	MemoryContextSwitchTo(oldcontext);
+
 	return 0;
 }
 
@@ -2669,6 +2706,87 @@ drop_unnamed_stmt(void)
 	}
 }
 
+/*
+ * get_portal_bind_parameters
+ * 		Get the string containing parameters data, is used for logging.
+ *
+ * Can return NULL if there are no parameters in the portal
+ * or the portal is not valid, or the text representations of the parameters are
+ * not available. If returning a non-NULL value, it allocates memory
+ * for the returned string in the current context, and it's the caller's
+ * responsibility to pfree() it if needed.
+ */
+char *
+get_portal_bind_parameters(ParamListInfo params)
+{
+	StringInfoData param_str;
+
+	/* No parameters to format */
+	if (!params || params->numParams == 0)
+		return NULL;
+
+	/*
+	 * We either need textual representation of parameters pre-calcualted,
+	 * or call potentially user-defined I/O functions to convert internal
+	 * representation into text, which cannot be done in an aborted xact
+	 */
+	if (!params->hasTextValues && IsAbortedTransactionBlockState())
+		return NULL;
+
+	initStringInfo(&param_str);
+
+	/* This code doesn't support dynamic param lists */
+	Assert(params->paramFetch == NULL);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *prm = &params->params[paramno];
+		char	   *pstring;
+		char	   *p;
+
+		appendStringInfo(&param_str, "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (prm->isnull)
+		{
+			appendStringInfoString(&param_str, "NULL");
+			continue;
+		}
+
+		if (params->hasTextValues)
+			pstring = prm->textValue;
+		else
+		{
+			Oid			typoutput;
+			bool		typisvarlena;
+
+			if (!OidIsValid(prm->ptype))
+			{
+				appendStringInfoString(&param_str, "UNKNOWN TYPE");
+				continue;
+			}
+
+			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
+			pstring = OidOutputFunctionCall(typoutput, prm->value);
+		}
+
+		appendStringInfoCharMacro(&param_str, '\'');
+		for (p = pstring; *p; p++)
+		{
+			if (*p == '\'') /* double single quotes */
+				appendStringInfoCharMacro(&param_str, *p);
+			appendStringInfoCharMacro(&param_str, *p);
+		}
+		appendStringInfoCharMacro(&param_str, '\'');
+
+		if (!params->hasTextValues)
+			pfree(pstring);
+	}
+
+	return param_str.data;
+}
+
 
 /* --------------------------------
  *		signal handler routines used in PostgresMain()
@@ -4022,10 +4140,11 @@ PostgresMain(int argc, char *argv[],
 		EmitErrorReport();
 
 		/*
-		 * Make sure debug_query_string gets reset before we possibly clobber
-		 * the storage it points at.
+		 * Make sure these get reset before we possibly clobber
+		 * the storages they point at.
 		 */
 		debug_query_string = NULL;
+		current_top_portal = NULL;
 
 		/*
 		 * Abort the current transaction in order to recover.
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 8b4720e..e18d9e5 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -76,6 +76,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 #include "utils/ps_status.h"
 
 
@@ -344,6 +345,7 @@ errstart(int elevel, const char *filename, int lineno,
 		{
 			error_context_stack = NULL;
 			debug_query_string = NULL;
+			current_top_portal = NULL;
 		}
 	}
 	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
@@ -2788,6 +2790,18 @@ write_csvlog(ErrorData *edata)
 	if (print_stmt && edata->cursorpos > 0)
 		appendStringInfo(&buf, "%d", edata->cursorpos);
 	appendStringInfoChar(&buf, ',');
+	if (print_stmt && log_parameters_on_error
+					&& PortalIsValid(current_top_portal))
+	{
+		char *param_values =
+			get_portal_bind_parameters(current_top_portal->portalParams);
+		if (param_values != NULL)
+		{
+			appendCSVLiteral(&buf, param_values);
+			pfree(param_values);
+		}
+	}
+	appendStringInfoChar(&buf, ',');
 
 	/* file error location */
 	if (Log_error_verbosity >= PGERROR_VERBOSE)
@@ -2944,6 +2958,18 @@ send_message_to_server_log(ErrorData *edata)
 		appendStringInfoString(&buf, _("STATEMENT:  "));
 		append_with_tabs(&buf, debug_query_string);
 		appendStringInfoChar(&buf, '\n');
+
+		if (log_parameters_on_error && PortalIsValid(current_top_portal))
+		{
+			char *param_values =
+				get_portal_bind_parameters(current_top_portal->portalParams);
+			if (param_values != NULL)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("PARAMETERS:  %s\n"), param_values);
+				pfree(param_values);
+			}
+		}
 	}
 
 #ifdef HAVE_SYSLOG
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index aa564d1..acd4f1e 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -481,6 +481,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1254,6 +1255,15 @@ static struct config_bool ConfigureNamesBool[] =
 		NULL, NULL, NULL
 	},
 	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
+	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
 			NULL
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index cccb5f1..61ec41a 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -528,6 +528,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd90466..316d3a2 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -93,6 +93,7 @@ typedef struct ParamExternData
 	bool		isnull;			/* is it NULL? */
 	uint16		pflags;			/* flag bits, see above */
 	Oid			ptype;			/* parameter's datatype, or 0 */
+	char	   *textValue;		/* textual representation for debug purposes */
 } ParamExternData;
 
 typedef struct ParamListInfoData *ParamListInfo;
@@ -116,6 +117,8 @@ typedef struct ParamListInfoData
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
 	int			numParams;		/* nominal/maximum # of Params represented */
+	bool		hasTextValues;	/* whether textValue for all non-null
+														params is populated */
 
 	/*
 	 * params[] may be of length zero if paramFetch is supplied; otherwise it
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index b367838..2cfa2ac 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -24,6 +24,7 @@
 #include "nodes/plannodes.h"
 #include "storage/procsignal.h"
 #include "utils/guc.h"
+#include "utils/portal.h"
 #include "utils/queryenvironment.h"
 
 
@@ -32,6 +33,8 @@
 
 extern CommandDest whereToSendOutput;
 extern PGDLLIMPORT const char *debug_query_string;
+extern PGDLLIMPORT Portal current_top_portal;
+
 extern int	max_stack_depth;
 extern int	PostAuthDelay;
 
@@ -83,6 +86,7 @@ extern long get_stack_depth_rlimit(void);
 extern void ResetUsage(void);
 extern void ShowUsage(const char *title);
 extern int	check_log_duration(char *msec_str, bool was_logged);
+extern char *get_portal_bind_parameters(ParamListInfo params);
 extern void set_debug_options(int debug_flag,
 				  GucContext context, GucSource source);
 extern bool set_plan_disabling_options(const char *arg,
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 2712a77..563dcea 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -232,6 +232,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 75f9471..437dc44 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6418,6 +6418,23 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether the statement is logged with bind parameter values. 
+        It adds some overhead, as postgres will cache textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged. The default is
+        <literal>off</literal>. Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index f5d5613..5e5ccf1 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -45,6 +45,7 @@ makeParamList(int numParams)
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
 	retval->numParams = numParams;
+	retval->hasTextValues = false;
 
 	return retval;
 }
@@ -58,6 +59,10 @@ makeParamList(int numParams)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * Since this function is never used for copying parameters into a top portal,
+ * we don't copy textual representations. Neither we set the hasTextValues
+ * flag, so noone will access them.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 44a59e1..3559163 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -86,6 +86,12 @@
  */
 const char *debug_query_string; /* client-supplied query string */
 
+/*
+ * The top-level portal that the client is immediately working with:
+ * creating, binding, executing, or all at one using simple protocol
+ */
+Portal current_top_portal = NULL;
+
 /* Note: whereToSendOutput is initialized for the bootstrap/standalone case */
 CommandDest whereToSendOutput = DestDebug;
 
@@ -1694,6 +1700,9 @@ exec_bind_message(StringInfo input_message)
 	else
 		portal = CreatePortal(portal_name, false, false);
 
+	Assert(current_top_portal == NULL);
+	current_top_portal = portal;
+
 	/*
 	 * Prepare to copy stuff into the portal's memory context.  We do all this
 	 * copying first, because it could possibly fail (out-of-memory) and we
@@ -1731,6 +1740,9 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* GUC value can change, so we remember its state to be consistent */
+		bool need_text_values = log_parameters_on_error;
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1798,9 +1810,31 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				if (pstring)
+				{
+					if (need_text_values)
+					{
+						if (pstring == pbuf.data)
+						{
+							/*
+							 * Copy textual representation to portal context.
+							 */
+							params->params[paramno].textValue =
+															pstrdup(pstring);
+						}
+						else
+						{
+							/* Reuse the result of encoding conversion for it */
+							params->params[paramno].textValue = pstring;
+						}
+					}
+					else
+					{
+						/* Free result of encoding conversion */
+						if (pstring != pbuf.data)
+							pfree(pstring);
+					}
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1826,6 +1860,22 @@ exec_bind_message(StringInfo input_message)
 							(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
 							 errmsg("incorrect binary data format in bind parameter %d",
 									paramno + 1)));
+
+				/*
+				 * Compute textual representation for further logging. We waste
+				 * some time and memory here, maybe one day we could skip
+				 * certain types like built-in primitives, which are safe to get
+				 * it calculated later in an aborted xact.
+				 */
+				if (!isNull && need_text_values)
+				{
+					Oid			typoutput;
+					bool		typisvarlena;
+
+					getTypeOutputInfo(ptype, &typoutput, &typisvarlena);
+					params->params[paramno].textValue =
+								OidOutputFunctionCall(typoutput, pval);
+				}
 			}
 			else
 			{
@@ -1850,10 +1900,22 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/*
+		 * only now we can safely set it, as we have textValue populated
+		 * for all non-null parameters
+		 */
+		params->hasTextValues = need_text_values;
 	}
 	else
 		params = NULL;
 
+	/*
+	 * Set portal parameters early for them to get logged if an error happens
+	 * on planning stage
+	 */
+	portal->portalParams = params;
+
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
@@ -1934,6 +1996,7 @@ exec_bind_message(StringInfo input_message)
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -1969,7 +2032,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 		ereport(ERROR,
 				(errcode(ERRCODE_UNDEFINED_CURSOR),
 				 errmsg("portal \"%s\" does not exist", portal_name)));
-
 	/*
 	 * If the original query was a null string, just return
 	 * EmptyQueryResponse.
@@ -1984,32 +2046,49 @@ exec_execute_message(const char *portal_name, long max_rows)
 	/* Does the portal contain a transaction command? */
 	is_xact_command = IsTransactionStmtList(portal->stmts);
 
-	/*
-	 * We must copy the sourceText and prepStmtName into MessageContext in
-	 * case the portal is destroyed during finish_xact_command. Can avoid the
-	 * copy if it's not an xact command, though.
-	 */
 	if (is_xact_command)
 	{
+		/*
+		 * We must copy the sourceText and prepStmtName into MessageContext in
+		 * case the portal is destroyed during finish_xact_command.
+		 */
 		sourceText = pstrdup(portal->sourceText);
 		if (portal->prepStmtName)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
 		/*
 		 * An xact command shouldn't have any parameters, which is a good
 		 * thing because they wouldn't be around after finish_xact_command.
 		 */
 		portalParams = NULL;
+
+		/*
+		 * We don't set current top portal for xact cmds, as
+		 * 1) the portal may be destroyed earlier than the error happens
+		 * 2) it anyway has no parameters in it to log
+		 */
+		Assert(current_top_portal == NULL);
 	}
 	else
 	{
+		/*
+		 * The portal will remain there until we leave the function, so it's
+		 * safe avoid copying and just to refer to the data in its memory
+		 * context instead
+		 */
 		sourceText = portal->sourceText;
 		if (portal->prepStmtName)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
+
+		/*
+		 * For non-xact commands, we remember the current portal and its bind
+		 * parameters for further use in logging
+		 */
+		Assert(current_top_portal == NULL);
+		current_top_portal = portal;
 		portalParams = portal->portalParams;
 	}
 
@@ -2158,6 +2237,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2299,61 +2379,18 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
-	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
+	/* Make sure any trash is generated in MessageContext */
+	MemoryContext oldcontext = MemoryContextSwitchTo(MessageContext);
+	char *params_message = get_portal_bind_parameters(params);
 
-		pfree(param_str.data);
-
-		MemoryContextSwitchTo(oldcontext);
+	if (params_message)
+	{
+		errdetail("parameters: %s", params_message);
+		pfree(params_message);
 	}
 
+	MemoryContextSwitchTo(oldcontext);
+
 	return 0;
 }
 
@@ -2671,6 +2708,87 @@ drop_unnamed_stmt(void)
 	}
 }
 
+/*
+ * get_portal_bind_parameters
+ * 		Get the string containing parameters data, is used for logging.
+ *
+ * Can return NULL if there are no parameters in the portal
+ * or the portal is not valid, or the text representations of the parameters are
+ * not available. If returning a non-NULL value, it allocates memory
+ * for the returned string in the current context, and it's the caller's
+ * responsibility to pfree() it if needed.
+ */
+char *
+get_portal_bind_parameters(ParamListInfo params)
+{
+	StringInfoData param_str;
+
+	/* No parameters to format */
+	if (!params || params->numParams == 0)
+		return NULL;
+
+	/*
+	 * We either need textual representation of parameters pre-calcualted,
+	 * or call potentially user-defined I/O functions to convert internal
+	 * representation into text, which cannot be done in an aborted xact
+	 */
+	if (!params->hasTextValues && IsAbortedTransactionBlockState())
+		return NULL;
+
+	initStringInfo(&param_str);
+
+	/* This code doesn't support dynamic param lists */
+	Assert(params->paramFetch == NULL);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *prm = &params->params[paramno];
+		char	   *pstring;
+		char	   *p;
+
+		appendStringInfo(&param_str, "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (prm->isnull)
+		{
+			appendStringInfoString(&param_str, "NULL");
+			continue;
+		}
+
+		if (params->hasTextValues)
+			pstring = prm->textValue;
+		else
+		{
+			Oid			typoutput;
+			bool		typisvarlena;
+
+			if (!OidIsValid(prm->ptype))
+			{
+				appendStringInfoString(&param_str, "UNKNOWN TYPE");
+				continue;
+			}
+
+			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
+			pstring = OidOutputFunctionCall(typoutput, prm->value);
+		}
+
+		appendStringInfoCharMacro(&param_str, '\'');
+		for (p = pstring; *p; p++)
+		{
+			if (*p == '\'') /* double single quotes */
+				appendStringInfoCharMacro(&param_str, *p);
+			appendStringInfoCharMacro(&param_str, *p);
+		}
+		appendStringInfoCharMacro(&param_str, '\'');
+
+		if (!params->hasTextValues)
+			pfree(pstring);
+	}
+
+	return param_str.data;
+}
+
 
 /* --------------------------------
  *		signal handler routines used in PostgresMain()
@@ -4024,10 +4142,11 @@ PostgresMain(int argc, char *argv[],
 		EmitErrorReport();
 
 		/*
-		 * Make sure debug_query_string gets reset before we possibly clobber
-		 * the storage it points at.
+		 * Make sure these get reset before we possibly clobber
+		 * the storages they point at.
 		 */
 		debug_query_string = NULL;
+		current_top_portal = NULL;
 
 		/*
 		 * Abort the current transaction in order to recover.
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 8b4720e..e18d9e5 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -76,6 +76,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 #include "utils/ps_status.h"
 
 
@@ -344,6 +345,7 @@ errstart(int elevel, const char *filename, int lineno,
 		{
 			error_context_stack = NULL;
 			debug_query_string = NULL;
+			current_top_portal = NULL;
 		}
 	}
 	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
@@ -2788,6 +2790,18 @@ write_csvlog(ErrorData *edata)
 	if (print_stmt && edata->cursorpos > 0)
 		appendStringInfo(&buf, "%d", edata->cursorpos);
 	appendStringInfoChar(&buf, ',');
+	if (print_stmt && log_parameters_on_error
+					&& PortalIsValid(current_top_portal))
+	{
+		char *param_values =
+			get_portal_bind_parameters(current_top_portal->portalParams);
+		if (param_values != NULL)
+		{
+			appendCSVLiteral(&buf, param_values);
+			pfree(param_values);
+		}
+	}
+	appendStringInfoChar(&buf, ',');
 
 	/* file error location */
 	if (Log_error_verbosity >= PGERROR_VERBOSE)
@@ -2944,6 +2958,18 @@ send_message_to_server_log(ErrorData *edata)
 		appendStringInfoString(&buf, _("STATEMENT:  "));
 		append_with_tabs(&buf, debug_query_string);
 		appendStringInfoChar(&buf, '\n');
+
+		if (log_parameters_on_error && PortalIsValid(current_top_portal))
+		{
+			char *param_values =
+				get_portal_bind_parameters(current_top_portal->portalParams);
+			if (param_values != NULL)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("PARAMETERS:  %s\n"), param_values);
+				pfree(param_values);
+			}
+		}
 	}
 
 #ifdef HAVE_SYSLOG
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index f7f726b..9034303 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -483,6 +483,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1296,6 +1297,15 @@ static struct config_bool ConfigureNamesBool[] =
 		NULL, NULL, NULL
 	},
 	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
+	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
 			NULL
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 77bb7c2..b21ca36 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -536,6 +536,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd90466..316d3a2 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -93,6 +93,7 @@ typedef struct ParamExternData
 	bool		isnull;			/* is it NULL? */
 	uint16		pflags;			/* flag bits, see above */
 	Oid			ptype;			/* parameter's datatype, or 0 */
+	char	   *textValue;		/* textual representation for debug purposes */
 } ParamExternData;
 
 typedef struct ParamListInfoData *ParamListInfo;
@@ -116,6 +117,8 @@ typedef struct ParamListInfoData
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
 	int			numParams;		/* nominal/maximum # of Params represented */
+	bool		hasTextValues;	/* whether textValue for all non-null
+														params is populated */
 
 	/*
 	 * params[] may be of length zero if paramFetch is supplied; otherwise it
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index b367838..2cfa2ac 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -24,6 +24,7 @@
 #include "nodes/plannodes.h"
 #include "storage/procsignal.h"
 #include "utils/guc.h"
+#include "utils/portal.h"
 #include "utils/queryenvironment.h"
 
 
@@ -32,6 +33,8 @@
 
 extern CommandDest whereToSendOutput;
 extern PGDLLIMPORT const char *debug_query_string;
+extern PGDLLIMPORT Portal current_top_portal;
+
 extern int	max_stack_depth;
 extern int	PostAuthDelay;
 
@@ -83,6 +86,7 @@ extern long get_stack_depth_rlimit(void);
 extern void ResetUsage(void);
 extern void ShowUsage(const char *title);
 extern int	check_log_duration(char *msec_str, bool was_logged);
+extern char *get_portal_bind_parameters(ParamListInfo params);
 extern void set_debug_options(int debug_flag,
 				  GucContext context, GucSource source);
 extern bool set_plan_disabling_options(const char *arg,
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 6c41eda..e5f8d39 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
diff --git a/src/test/README b/src/test/README
index b5ccfc0..22e624d 100644
--- a/src/test/README
+++ b/src/test/README
@@ -12,8 +12,7 @@ authentication/
   Tests for authentication
 
 examples/
-  Demonstration programs for libpq that double as regression tests via
-  "make check"
+  Demonstration programs for libpq that double as regression tests
 
 isolation/
   Tests for concurrent behavior at the SQL level
diff --git a/src/test/examples/testlibpq3.c b/src/test/examples/testlibpq3.c
index c3b524c..3b76d66 100644
--- a/src/test/examples/testlibpq3.c
+++ b/src/test/examples/testlibpq3.c
@@ -42,7 +42,6 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
-
 static void
 exit_nicely(PGconn *conn)
 {
@@ -116,9 +115,9 @@ main(int argc, char **argv)
 	const char *conninfo;
 	PGconn	   *conn;
 	PGresult   *res;
-	const char *paramValues[1];
-	int			paramLengths[1];
-	int			paramFormats[1];
+	const char *paramValues[2];
+	int			paramLengths[2];
+	int			paramFormats[2];
 	uint32_t	binaryIntVal;
 
 	/*
@@ -224,6 +223,52 @@ main(int argc, char **argv)
 
 	PQclear(res);
 
+	/*
+	 * In the third example we transmit parameters in different forms, make
+	 * a statement fail and check how logging parameters on error works.
+	 */
+	/* Set always-secure search path, so malicious users can't take control. */
+
+	res = PQexec(conn, "SET log_parameters_on_error = on");
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	paramValues[0] = (char *) &binaryIntVal;
+	paramLengths[0] = sizeof(binaryIntVal);
+	paramFormats[0] = 1;		/* binary */
+	paramValues[1] = "2";
+	paramLengths[1] = strlen(paramValues[1]) + 1;
+	paramFormats[1] = 0;		/* text */
+	res = PQexecParams(conn,
+					   /*
+						* always divide by zero,
+						* but deduce it only when executing
+						*/
+					   "SELECT 1 / (random() / 2)::int + $1::int + $2::int",
+					   2,		/* two params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero expected, got an error message from server: %s"
+				"Please make sure it has been logged "
+					"with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
 	/* close the connection to the database and cleanup */
 	PQfinish(conn);
 

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index c91e3e1550..9f2e9bae33 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6423,6 +6423,23 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether the statement is logged with bind parameter values. 
+        It adds some overhead, as postgres will cache textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged. The default is
+        <literal>off</literal>. Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index f5d56138ee..5e5ccf1a4f 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -45,6 +45,7 @@ makeParamList(int numParams)
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
 	retval->numParams = numParams;
+	retval->hasTextValues = false;
 
 	return retval;
 }
@@ -58,6 +59,10 @@ makeParamList(int numParams)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * Since this function is never used for copying parameters into a top portal,
+ * we don't copy textual representations. Neither we set the hasTextValues
+ * flag, so noone will access them.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 44a59e1d4f..3559163ac3 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -86,6 +86,12 @@
  */
 const char *debug_query_string; /* client-supplied query string */
 
+/*
+ * The top-level portal that the client is immediately working with:
+ * creating, binding, executing, or all at one using simple protocol
+ */
+Portal current_top_portal = NULL;
+
 /* Note: whereToSendOutput is initialized for the bootstrap/standalone case */
 CommandDest whereToSendOutput = DestDebug;
 
@@ -1694,6 +1700,9 @@ exec_bind_message(StringInfo input_message)
 	else
 		portal = CreatePortal(portal_name, false, false);
 
+	Assert(current_top_portal == NULL);
+	current_top_portal = portal;
+
 	/*
 	 * Prepare to copy stuff into the portal's memory context.  We do all this
 	 * copying first, because it could possibly fail (out-of-memory) and we
@@ -1731,6 +1740,9 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* GUC value can change, so we remember its state to be consistent */
+		bool need_text_values = log_parameters_on_error;
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1798,9 +1810,31 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				if (pstring)
+				{
+					if (need_text_values)
+					{
+						if (pstring == pbuf.data)
+						{
+							/*
+							 * Copy textual representation to portal context.
+							 */
+							params->params[paramno].textValue =
+															pstrdup(pstring);
+						}
+						else
+						{
+							/* Reuse the result of encoding conversion for it */
+							params->params[paramno].textValue = pstring;
+						}
+					}
+					else
+					{
+						/* Free result of encoding conversion */
+						if (pstring != pbuf.data)
+							pfree(pstring);
+					}
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1826,6 +1860,22 @@ exec_bind_message(StringInfo input_message)
 							(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
 							 errmsg("incorrect binary data format in bind parameter %d",
 									paramno + 1)));
+
+				/*
+				 * Compute textual representation for further logging. We waste
+				 * some time and memory here, maybe one day we could skip
+				 * certain types like built-in primitives, which are safe to get
+				 * it calculated later in an aborted xact.
+				 */
+				if (!isNull && need_text_values)
+				{
+					Oid			typoutput;
+					bool		typisvarlena;
+
+					getTypeOutputInfo(ptype, &typoutput, &typisvarlena);
+					params->params[paramno].textValue =
+								OidOutputFunctionCall(typoutput, pval);
+				}
 			}
 			else
 			{
@@ -1850,10 +1900,22 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/*
+		 * only now we can safely set it, as we have textValue populated
+		 * for all non-null parameters
+		 */
+		params->hasTextValues = need_text_values;
 	}
 	else
 		params = NULL;
 
+	/*
+	 * Set portal parameters early for them to get logged if an error happens
+	 * on planning stage
+	 */
+	portal->portalParams = params;
+
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
@@ -1934,6 +1996,7 @@ exec_bind_message(StringInfo input_message)
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -1969,7 +2032,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 		ereport(ERROR,
 				(errcode(ERRCODE_UNDEFINED_CURSOR),
 				 errmsg("portal \"%s\" does not exist", portal_name)));
-
 	/*
 	 * If the original query was a null string, just return
 	 * EmptyQueryResponse.
@@ -1984,32 +2046,49 @@ exec_execute_message(const char *portal_name, long max_rows)
 	/* Does the portal contain a transaction command? */
 	is_xact_command = IsTransactionStmtList(portal->stmts);
 
-	/*
-	 * We must copy the sourceText and prepStmtName into MessageContext in
-	 * case the portal is destroyed during finish_xact_command. Can avoid the
-	 * copy if it's not an xact command, though.
-	 */
 	if (is_xact_command)
 	{
+		/*
+		 * We must copy the sourceText and prepStmtName into MessageContext in
+		 * case the portal is destroyed during finish_xact_command.
+		 */
 		sourceText = pstrdup(portal->sourceText);
 		if (portal->prepStmtName)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
 		/*
 		 * An xact command shouldn't have any parameters, which is a good
 		 * thing because they wouldn't be around after finish_xact_command.
 		 */
 		portalParams = NULL;
+
+		/*
+		 * We don't set current top portal for xact cmds, as
+		 * 1) the portal may be destroyed earlier than the error happens
+		 * 2) it anyway has no parameters in it to log
+		 */
+		Assert(current_top_portal == NULL);
 	}
 	else
 	{
+		/*
+		 * The portal will remain there until we leave the function, so it's
+		 * safe avoid copying and just to refer to the data in its memory
+		 * context instead
+		 */
 		sourceText = portal->sourceText;
 		if (portal->prepStmtName)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
+
+		/*
+		 * For non-xact commands, we remember the current portal and its bind
+		 * parameters for further use in logging
+		 */
+		Assert(current_top_portal == NULL);
+		current_top_portal = portal;
 		portalParams = portal->portalParams;
 	}
 
@@ -2158,6 +2237,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2299,61 +2379,18 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
-	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
+	/* Make sure any trash is generated in MessageContext */
+	MemoryContext oldcontext = MemoryContextSwitchTo(MessageContext);
+	char *params_message = get_portal_bind_parameters(params);
 
-		pfree(param_str.data);
-
-		MemoryContextSwitchTo(oldcontext);
+	if (params_message)
+	{
+		errdetail("parameters: %s", params_message);
+		pfree(params_message);
 	}
 
+	MemoryContextSwitchTo(oldcontext);
+
 	return 0;
 }
 
@@ -2671,6 +2708,87 @@ drop_unnamed_stmt(void)
 	}
 }
 
+/*
+ * get_portal_bind_parameters
+ * 		Get the string containing parameters data, is used for logging.
+ *
+ * Can return NULL if there are no parameters in the portal
+ * or the portal is not valid, or the text representations of the parameters are
+ * not available. If returning a non-NULL value, it allocates memory
+ * for the returned string in the current context, and it's the caller's
+ * responsibility to pfree() it if needed.
+ */
+char *
+get_portal_bind_parameters(ParamListInfo params)
+{
+	StringInfoData param_str;
+
+	/* No parameters to format */
+	if (!params || params->numParams == 0)
+		return NULL;
+
+	/*
+	 * We either need textual representation of parameters pre-calcualted,
+	 * or call potentially user-defined I/O functions to convert internal
+	 * representation into text, which cannot be done in an aborted xact
+	 */
+	if (!params->hasTextValues && IsAbortedTransactionBlockState())
+		return NULL;
+
+	initStringInfo(&param_str);
+
+	/* This code doesn't support dynamic param lists */
+	Assert(params->paramFetch == NULL);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *prm = &params->params[paramno];
+		char	   *pstring;
+		char	   *p;
+
+		appendStringInfo(&param_str, "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (prm->isnull)
+		{
+			appendStringInfoString(&param_str, "NULL");
+			continue;
+		}
+
+		if (params->hasTextValues)
+			pstring = prm->textValue;
+		else
+		{
+			Oid			typoutput;
+			bool		typisvarlena;
+
+			if (!OidIsValid(prm->ptype))
+			{
+				appendStringInfoString(&param_str, "UNKNOWN TYPE");
+				continue;
+			}
+
+			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
+			pstring = OidOutputFunctionCall(typoutput, prm->value);
+		}
+
+		appendStringInfoCharMacro(&param_str, '\'');
+		for (p = pstring; *p; p++)
+		{
+			if (*p == '\'') /* double single quotes */
+				appendStringInfoCharMacro(&param_str, *p);
+			appendStringInfoCharMacro(&param_str, *p);
+		}
+		appendStringInfoCharMacro(&param_str, '\'');
+
+		if (!params->hasTextValues)
+			pfree(pstring);
+	}
+
+	return param_str.data;
+}
+
 
 /* --------------------------------
  *		signal handler routines used in PostgresMain()
@@ -4024,10 +4142,11 @@ PostgresMain(int argc, char *argv[],
 		EmitErrorReport();
 
 		/*
-		 * Make sure debug_query_string gets reset before we possibly clobber
-		 * the storage it points at.
+		 * Make sure these get reset before we possibly clobber
+		 * the storages they point at.
 		 */
 		debug_query_string = NULL;
+		current_top_portal = NULL;
 
 		/*
 		 * Abort the current transaction in order to recover.
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 8b4720ef3a..e18d9e59c8 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -76,6 +76,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 #include "utils/ps_status.h"
 
 
@@ -344,6 +345,7 @@ errstart(int elevel, const char *filename, int lineno,
 		{
 			error_context_stack = NULL;
 			debug_query_string = NULL;
+			current_top_portal = NULL;
 		}
 	}
 	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
@@ -2788,6 +2790,18 @@ write_csvlog(ErrorData *edata)
 	if (print_stmt && edata->cursorpos > 0)
 		appendStringInfo(&buf, "%d", edata->cursorpos);
 	appendStringInfoChar(&buf, ',');
+	if (print_stmt && log_parameters_on_error
+					&& PortalIsValid(current_top_portal))
+	{
+		char *param_values =
+			get_portal_bind_parameters(current_top_portal->portalParams);
+		if (param_values != NULL)
+		{
+			appendCSVLiteral(&buf, param_values);
+			pfree(param_values);
+		}
+	}
+	appendStringInfoChar(&buf, ',');
 
 	/* file error location */
 	if (Log_error_verbosity >= PGERROR_VERBOSE)
@@ -2944,6 +2958,18 @@ send_message_to_server_log(ErrorData *edata)
 		appendStringInfoString(&buf, _("STATEMENT:  "));
 		append_with_tabs(&buf, debug_query_string);
 		appendStringInfoChar(&buf, '\n');
+
+		if (log_parameters_on_error && PortalIsValid(current_top_portal))
+		{
+			char *param_values =
+				get_portal_bind_parameters(current_top_portal->portalParams);
+			if (param_values != NULL)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("PARAMETERS:  %s\n"), param_values);
+				pfree(param_values);
+			}
+		}
 	}
 
 #ifdef HAVE_SYSLOG
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 631f16f5fe..2e0b265f4b 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -483,6 +483,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1294,6 +1295,15 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
+	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
 	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index cfad86c02a..02e60b3bd2 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -536,6 +536,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd9046619c..316d3a2888 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -93,6 +93,7 @@ typedef struct ParamExternData
 	bool		isnull;			/* is it NULL? */
 	uint16		pflags;			/* flag bits, see above */
 	Oid			ptype;			/* parameter's datatype, or 0 */
+	char	   *textValue;		/* textual representation for debug purposes */
 } ParamExternData;
 
 typedef struct ParamListInfoData *ParamListInfo;
@@ -116,6 +117,8 @@ typedef struct ParamListInfoData
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
 	int			numParams;		/* nominal/maximum # of Params represented */
+	bool		hasTextValues;	/* whether textValue for all non-null
+														params is populated */
 
 	/*
 	 * params[] may be of length zero if paramFetch is supplied; otherwise it
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index ec21f7e45c..ecd6a93e2c 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -19,6 +19,7 @@
 #include "nodes/plannodes.h"
 #include "storage/procsignal.h"
 #include "utils/guc.h"
+#include "utils/portal.h"
 #include "utils/queryenvironment.h"
 
 
@@ -27,6 +28,8 @@
 
 extern CommandDest whereToSendOutput;
 extern PGDLLIMPORT const char *debug_query_string;
+extern PGDLLIMPORT Portal current_top_portal;
+
 extern int	max_stack_depth;
 extern int	PostAuthDelay;
 
@@ -78,6 +81,7 @@ extern long get_stack_depth_rlimit(void);
 extern void ResetUsage(void);
 extern void ShowUsage(const char *title);
 extern int	check_log_duration(char *msec_str, bool was_logged);
+extern char *get_portal_bind_parameters(ParamListInfo params);
 extern void set_debug_options(int debug_flag,
 							  GucContext context, GucSource source);
 extern bool set_plan_disabling_options(const char *arg,
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index e709177c37..125dc13a31 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
diff --git a/src/test/README b/src/test/README
index b5ccfc0cf6..22e624d8ba 100644
--- a/src/test/README
+++ b/src/test/README
@@ -12,8 +12,7 @@ authentication/
   Tests for authentication
 
 examples/
-  Demonstration programs for libpq that double as regression tests via
-  "make check"
+  Demonstration programs for libpq that double as regression tests
 
 isolation/
   Tests for concurrent behavior at the SQL level
diff --git a/src/test/examples/testlibpq3.c b/src/test/examples/testlibpq3.c
index c3b524cfdf..3b76d66e7d 100644
--- a/src/test/examples/testlibpq3.c
+++ b/src/test/examples/testlibpq3.c
@@ -42,7 +42,6 @@
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
-
 static void
 exit_nicely(PGconn *conn)
 {
@@ -116,9 +115,9 @@ main(int argc, char **argv)
 	const char *conninfo;
 	PGconn	   *conn;
 	PGresult   *res;
-	const char *paramValues[1];
-	int			paramLengths[1];
-	int			paramFormats[1];
+	const char *paramValues[2];
+	int			paramLengths[2];
+	int			paramFormats[2];
 	uint32_t	binaryIntVal;
 
 	/*
@@ -224,6 +223,52 @@ main(int argc, char **argv)
 
 	PQclear(res);
 
+	/*
+	 * In the third example we transmit parameters in different forms, make
+	 * a statement fail and check how logging parameters on error works.
+	 */
+	/* Set always-secure search path, so malicious users can't take control. */
+
+	res = PQexec(conn, "SET log_parameters_on_error = on");
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	paramValues[0] = (char *) &binaryIntVal;
+	paramLengths[0] = sizeof(binaryIntVal);
+	paramFormats[0] = 1;		/* binary */
+	paramValues[1] = "2";
+	paramLengths[1] = strlen(paramValues[1]) + 1;
+	paramFormats[1] = 0;		/* text */
+	res = PQexecParams(conn,
+					   /*
+						* always divide by zero,
+						* but deduce it only when executing
+						*/
+					   "SELECT 1 / (random() / 2)::int + $1::int + $2::int",
+					   2,		/* two params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero expected, got an error message from server: %s"
+				"Please make sure it has been logged "
+					"with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
 	/* close the connection to the database and cleanup */
 	PQfinish(conn);
 

From 19c80d631694366e8098a564ba347fb1e937056b Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Wed, 18 Sep 2019 16:56:42 -0300
Subject: [PATCH v10] Allow logging of portal parameters on error

---
 doc/src/sgml/config.sgml                      |  17 ++
 src/backend/nodes/params.c                    |   3 +
 src/backend/tcop/postgres.c                   | 233 +++++++++++++-----
 src/backend/utils/error/elog.c                |  28 +++
 src/backend/utils/misc/guc.c                  |  10 +
 src/backend/utils/misc/postgresql.conf.sample |   1 +
 src/include/nodes/params.h                    |   3 +
 src/include/tcop/tcopprot.h                   |   4 +
 src/include/utils/guc.h                       |   1 +
 src/test/README                               |   3 +-
 src/test/examples/Makefile                    |   2 +-
 src/test/examples/testlibpq5.c                | 116 +++++++++
 12 files changed, 355 insertions(+), 66 deletions(-)
 create mode 100644 src/test/examples/testlibpq5.c

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 6612f95f9f..81dfee5fe7 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6414,6 +6414,23 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether the statement is logged with bind parameter values. 
+        It adds some overhead, as postgres will cache textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged. The default is
+        <literal>off</literal>. Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index cf4387e40f..00ad6347c7 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -45,6 +45,7 @@ makeParamList(int numParams)
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
 	retval->numParams = numParams;
+	retval->hasTextValues = false;
 
 	return retval;
 }
@@ -58,6 +59,8 @@ makeParamList(int numParams)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * We don't bother copying text values, since no caller needs that at present.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index e8d8e6f828..ec1e4092f5 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -86,6 +86,12 @@
  */
 const char *debug_query_string; /* client-supplied query string */
 
+/*
+ * The top-level portal that the client is immediately working with:
+ * creating, binding, executing, or all at one using simple protocol
+ */
+Portal current_top_portal = NULL;
+
 /* Note: whereToSendOutput is initialized for the bootstrap/standalone case */
 CommandDest whereToSendOutput = DestDebug;
 
@@ -1714,6 +1720,9 @@ exec_bind_message(StringInfo input_message)
 	else
 		portal = CreatePortal(portal_name, false, false);
 
+	Assert(current_top_portal == NULL);
+	current_top_portal = portal;
+
 	/*
 	 * Prepare to copy stuff into the portal's memory context.  We do all this
 	 * copying first, because it could possibly fail (out-of-memory) and we
@@ -1751,6 +1760,9 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* GUC value can change, so we remember its state to be consistent */
+		bool need_text_values = log_parameters_on_error;
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1818,9 +1830,18 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				/*
+				 * If we need the parameter string, keep it -- possibly making
+				 * a copy first, if necessary.  Otherwise get rid of it.
+				 */
+				if (pstring)
+				{
+					if (need_text_values)
+						params->params[paramno].textValue =
+							pstring == pbuf.data ? pstrdup(pstring) : pstring;
+					else if (pstring != pbuf.data)
+						pfree(pstring);
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1846,6 +1867,23 @@ exec_bind_message(StringInfo input_message)
 							(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
 							 errmsg("incorrect binary data format in bind parameter %d",
 									paramno + 1)));
+
+				/*
+				 * Compute textual representation for further logging.
+				 *
+				 * This could be optimized for certain built-in types, for
+				 * which the output function is safe to call even in an
+				 * aborted transaction.
+				 */
+				if (!isNull && need_text_values)
+				{
+					Oid			typoutput;
+					bool		typisvarlena;
+
+					getTypeOutputInfo(ptype, &typoutput, &typisvarlena);
+					params->params[paramno].textValue =
+						OidOutputFunctionCall(typoutput, pval);
+				}
 			}
 			else
 			{
@@ -1870,10 +1908,19 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/* Only now can we safely set this. */
+		params->hasTextValues = need_text_values;
 	}
 	else
 		params = NULL;
 
+	/*
+	 * Set portal parameters early for them to get logged if an error happens
+	 * on planning stage
+	 */
+	portal->portalParams = params;
+
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
@@ -1954,6 +2001,7 @@ exec_bind_message(StringInfo input_message)
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2004,32 +2052,49 @@ exec_execute_message(const char *portal_name, long max_rows)
 	/* Does the portal contain a transaction command? */
 	is_xact_command = IsTransactionStmtList(portal->stmts);
 
-	/*
-	 * We must copy the sourceText and prepStmtName into MessageContext in
-	 * case the portal is destroyed during finish_xact_command. Can avoid the
-	 * copy if it's not an xact command, though.
-	 */
 	if (is_xact_command)
 	{
+		/*
+		 * We must copy the sourceText and prepStmtName into MessageContext in
+		 * case the portal is destroyed during finish_xact_command.
+		 */
 		sourceText = pstrdup(portal->sourceText);
 		if (portal->prepStmtName)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
 		/*
 		 * An xact command shouldn't have any parameters, which is a good
 		 * thing because they wouldn't be around after finish_xact_command.
 		 */
 		portalParams = NULL;
+
+		/*
+		 * We don't set current top portal for xact cmds, as
+		 * 1) the portal may be destroyed earlier than the error happens
+		 * 2) it anyway has no parameters in it to log
+		 */
+		Assert(current_top_portal == NULL);
 	}
 	else
 	{
+		/*
+		 * The portal will remain there until we leave the function, so it's
+		 * safe avoid copying and just to refer to the data in its memory
+		 * context instead
+		 */
 		sourceText = portal->sourceText;
 		if (portal->prepStmtName)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
+
+		/*
+		 * For non-xact commands, we remember the current portal and its bind
+		 * parameters for further use in logging
+		 */
+		Assert(current_top_portal == NULL);
+		current_top_portal = portal;
 		portalParams = portal->portalParams;
 	}
 
@@ -2178,6 +2243,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2306,61 +2372,21 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
+	MemoryContext oldcontext;
+	char	   *params_message;
+
+	/* Make sure any trash is generated in MessageContext */
+	oldcontext = MemoryContextSwitchTo(MessageContext);
+	params_message = get_portal_bind_params(params);
+
+	if (params_message)
 	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
-
-		pfree(param_str.data);
-
-		MemoryContextSwitchTo(oldcontext);
+		errdetail("parameters: %s", params_message);
+		pfree(params_message);
 	}
 
+	MemoryContextSwitchTo(oldcontext);
+
 	return 0;
 }
 
@@ -2678,6 +2704,86 @@ drop_unnamed_stmt(void)
 	}
 }
 
+/*
+ * get_portal_bind_params
+ * 		Get a string containing parameters data -- used for logging.
+ *
+ * Can return NULL if there are no parameters in the portal or the portal is
+ * not valid, or the text representations of the parameters are not available.
+ * If returning a non-NULL value, it allocates memory for the returned string
+ * in the current context, and it's the caller's responsibility to pfree() it.
+ */
+char *
+get_portal_bind_params(ParamListInfo params)
+{
+	StringInfoData param_str;
+
+	/* No parameters to format */
+	if (!params || params->numParams == 0)
+		return NULL;
+
+	/*
+	 * We either need textual representation of parameters pre-calculated, or
+	 * call potentially user-defined I/O functions to convert the internal
+	 * representation into text, which cannot be done in an aborted xact
+	 */
+	if (!params->hasTextValues && IsAbortedTransactionBlockState())
+		return NULL;
+
+	initStringInfo(&param_str);
+
+	/* This code doesn't support dynamic param lists */
+	Assert(params->paramFetch == NULL);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *prm = &params->params[paramno];
+		char	   *pstring;
+		char	   *p;
+
+		appendStringInfo(&param_str, "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (prm->isnull)
+		{
+			appendStringInfoString(&param_str, "NULL");
+			continue;
+		}
+
+		if (params->hasTextValues)
+			pstring = prm->textValue;
+		else
+		{
+			Oid			typoutput;
+			bool		typisvarlena;
+
+			if (!OidIsValid(prm->ptype))
+			{
+				appendStringInfoString(&param_str, "UNKNOWN TYPE");
+				continue;
+			}
+
+			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
+			pstring = OidOutputFunctionCall(typoutput, prm->value);
+		}
+
+		appendStringInfoCharMacro(&param_str, '\'');
+		for (p = pstring; *p; p++)
+		{
+			if (*p == '\'') /* double single quotes */
+				appendStringInfoCharMacro(&param_str, *p);
+			appendStringInfoCharMacro(&param_str, *p);
+		}
+		appendStringInfoCharMacro(&param_str, '\'');
+
+		if (!params->hasTextValues)
+			pfree(pstring);
+	}
+
+	return param_str.data;
+}
+
 
 /* --------------------------------
  *		signal handler routines used in PostgresMain()
@@ -4031,10 +4137,11 @@ PostgresMain(int argc, char *argv[],
 		EmitErrorReport();
 
 		/*
-		 * Make sure debug_query_string gets reset before we possibly clobber
-		 * the storage it points at.
+		 * Make sure these get reset before we possibly clobber
+		 * the storages they point at.
 		 */
 		debug_query_string = NULL;
+		current_top_portal = NULL;
 
 		/*
 		 * Abort the current transaction in order to recover.
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 8b4720ef3a..40896a2d09 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -76,6 +76,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 #include "utils/ps_status.h"
 
 
@@ -344,6 +345,7 @@ errstart(int elevel, const char *filename, int lineno,
 		{
 			error_context_stack = NULL;
 			debug_query_string = NULL;
+			current_top_portal = NULL;
 		}
 	}
 	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
@@ -2788,6 +2790,19 @@ write_csvlog(ErrorData *edata)
 	if (print_stmt && edata->cursorpos > 0)
 		appendStringInfo(&buf, "%d", edata->cursorpos);
 	appendStringInfoChar(&buf, ',');
+	if (print_stmt && log_parameters_on_error &&
+		PortalIsValid(current_top_portal))
+	{
+		char *params;
+
+		params = get_portal_bind_params(current_top_portal->portalParams);
+		if (params != NULL)
+		{
+			appendCSVLiteral(&buf, params);
+			pfree(params);
+		}
+	}
+	appendStringInfoChar(&buf, ',');
 
 	/* file error location */
 	if (Log_error_verbosity >= PGERROR_VERBOSE)
@@ -2944,6 +2959,19 @@ send_message_to_server_log(ErrorData *edata)
 		appendStringInfoString(&buf, _("STATEMENT:  "));
 		append_with_tabs(&buf, debug_query_string);
 		appendStringInfoChar(&buf, '\n');
+
+		if (log_parameters_on_error && PortalIsValid(current_top_portal))
+		{
+			char *params;
+
+			params = get_portal_bind_params(current_top_portal->portalParams);
+			if (params != NULL)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("PARAMETERS:  %s\n"), params);
+				pfree(params);
+			}
+		}
 	}
 
 #ifdef HAVE_SYSLOG
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 90ffd89339..d426272be3 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -483,6 +483,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1293,6 +1294,15 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
+	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
 	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 0fc23e3a61..fccfff3a03 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -532,6 +532,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd9046619c..316d3a2888 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -93,6 +93,7 @@ typedef struct ParamExternData
 	bool		isnull;			/* is it NULL? */
 	uint16		pflags;			/* flag bits, see above */
 	Oid			ptype;			/* parameter's datatype, or 0 */
+	char	   *textValue;		/* textual representation for debug purposes */
 } ParamExternData;
 
 typedef struct ParamListInfoData *ParamListInfo;
@@ -116,6 +117,8 @@ typedef struct ParamListInfoData
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
 	int			numParams;		/* nominal/maximum # of Params represented */
+	bool		hasTextValues;	/* whether textValue for all non-null
+														params is populated */
 
 	/*
 	 * params[] may be of length zero if paramFetch is supplied; otherwise it
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index ec21f7e45c..ad6517414b 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -19,6 +19,7 @@
 #include "nodes/plannodes.h"
 #include "storage/procsignal.h"
 #include "utils/guc.h"
+#include "utils/portal.h"
 #include "utils/queryenvironment.h"
 
 
@@ -27,6 +28,8 @@
 
 extern CommandDest whereToSendOutput;
 extern PGDLLIMPORT const char *debug_query_string;
+extern PGDLLIMPORT Portal current_top_portal;
+
 extern int	max_stack_depth;
 extern int	PostAuthDelay;
 
@@ -78,6 +81,7 @@ extern long get_stack_depth_rlimit(void);
 extern void ResetUsage(void);
 extern void ShowUsage(const char *title);
 extern int	check_log_duration(char *msec_str, bool was_logged);
+extern char *get_portal_bind_params(ParamListInfo params);
 extern void set_debug_options(int debug_flag,
 							  GucContext context, GucSource source);
 extern bool set_plan_disabling_options(const char *arg,
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 6791e0cbc2..57acc28ef9 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
diff --git a/src/test/README b/src/test/README
index b5ccfc0cf6..22e624d8ba 100644
--- a/src/test/README
+++ b/src/test/README
@@ -12,8 +12,7 @@ authentication/
   Tests for authentication
 
 examples/
-  Demonstration programs for libpq that double as regression tests via
-  "make check"
+  Demonstration programs for libpq that double as regression tests
 
 isolation/
   Tests for concurrent behavior at the SQL level
diff --git a/src/test/examples/Makefile b/src/test/examples/Makefile
index a67f456904..0407ca60bc 100644
--- a/src/test/examples/Makefile
+++ b/src/test/examples/Makefile
@@ -14,7 +14,7 @@ override CPPFLAGS := -I$(libpq_srcdir) $(CPPFLAGS)
 LDFLAGS_INTERNAL += $(libpq_pgport)
 
 
-PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlo testlo64
+PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlibpq5 testlo testlo64
 
 all: $(PROGS)
 
diff --git a/src/test/examples/testlibpq5.c b/src/test/examples/testlibpq5.c
new file mode 100644
index 0000000000..69b65c512b
--- /dev/null
+++ b/src/test/examples/testlibpq5.c
@@ -0,0 +1,116 @@
+/*
+ * src/test/examples/testlibpq5.c
+ *
+ * testlibpq5.c
+ *		Test logging of statement parameters in case of errors.
+ */
+
+#ifdef WIN32
+#include <windows.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/types.h>
+#include "libpq-fe.h"
+
+static void
+exit_nicely(PGconn *conn)
+{
+	PQfinish(conn);
+	exit(1);
+}
+
+int
+main(int argc, char **argv)
+{
+	const char *conninfo;
+	PGconn	   *conn;
+	PGresult   *res;
+	const char *paramValues[3];
+	int			paramLengths[3];
+	int			paramFormats[3];
+	uint32_t	binaryIntVal;
+
+	/*
+	 * If the user supplies a parameter on the command line, use it as the
+	 * conninfo string; otherwise default to setting dbname=postgres and using
+	 * environment variables or defaults for all other connection parameters.
+	 */
+	if (argc > 1)
+		conninfo = argv[1];
+	else
+		conninfo = "dbname = postgres";
+
+	/* Make a connection to the database */
+	conn = PQconnectdb(conninfo);
+
+	/* Check to see that the backend connection was successfully made */
+	if (PQstatus(conn) != CONNECTION_OK)
+	{
+		fprintf(stderr, "Connection to database failed: %s",
+				PQerrorMessage(conn));
+		exit_nicely(conn);
+	}
+
+	/* Set always-secure search path, so malicious users can't take control. */
+	res = PQexec(conn,
+				 "SELECT pg_catalog.set_config('search_path', '', false)");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/*
+	 * Transmit parameters in different forms and make a statement fail.  User
+	 * can then verify the server log.
+	 */
+	res = PQexec(conn, "SET log_parameters_on_error = on");
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	paramValues[0] = (char *) &binaryIntVal;
+	paramLengths[0] = sizeof(binaryIntVal);
+	paramFormats[0] = 1;		/* binary */
+	paramValues[1] = "2";
+	paramLengths[1] = strlen(paramValues[1]) + 1;
+	paramFormats[1] = 0;		/* text */
+	paramValues[2] = (char *) "everyone's little $$ in \"dollar\"";
+	paramLengths[2] = strlen(paramValues[2]) + 1;
+	paramFormats[2] = 0;		/* text */
+	/* divide by zero -- but server won't realize until execution */
+	res = PQexecParams(conn,
+					   "SELECT 1 / (random() / 2)::int + $1::int + $2::int, $3::text",
+					   3,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero expected, got an error message from server: %s\n"
+		   "Please make sure it has been logged with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* close the connection to the database and cleanup */
+	PQfinish(conn);
+
+	return 0;
+}
-- 
2.17.1

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 6612f95f9f..81dfee5fe7 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6414,6 +6414,23 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether the statement is logged with bind parameter values. 
+        It adds some overhead, as postgres will cache textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged. The default is
+        <literal>off</literal>. Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 7e0a041fab..7692ea551b 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -406,7 +406,7 @@ EvaluateParams(PreparedStatement *pstmt, List *params,
 		prm->value = ExecEvalExprSwitchContext(n,
 											   GetPerTupleExprContext(estate),
 											   &prm->isnull);
-
+		prm->textValue = NULL;
 		i++;
 	}
 
diff --git a/src/backend/executor/functions.c b/src/backend/executor/functions.c
index 83337c2eed..92fcee8b19 100644
--- a/src/backend/executor/functions.c
+++ b/src/backend/executor/functions.c
@@ -925,6 +925,7 @@ postquel_sub_params(SQLFunctionCachePtr fcache,
 			prm->isnull = fcinfo->args[i].isnull;
 			prm->pflags = 0;
 			prm->ptype = fcache->pinfo->argtypes[i];
+			prm->textValue = NULL;
 		}
 	}
 	else
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 2c0ae395ba..f6b4246b47 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -2458,6 +2458,7 @@ _SPI_convert_params(int nargs, Oid *argtypes,
 			prm->isnull = (Nulls && Nulls[i] == 'n');
 			prm->pflags = PARAM_FLAG_CONST;
 			prm->ptype = argtypes[i];
+			prm->textValue = NULL;
 		}
 	}
 	else
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index cf4387e40f..bf8e3705af 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -45,6 +45,7 @@ makeParamList(int numParams)
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
 	retval->numParams = numParams;
+	retval->hasTextValues = false;
 
 	return retval;
 }
@@ -91,6 +92,9 @@ copyParamList(ParamListInfo from)
 			continue;
 		get_typlenbyval(nprm->ptype, &typLen, &typByVal);
 		nprm->value = datumCopy(nprm->value, typByVal, typLen);
+
+		/* We don't copy text values, as no caller needs that at present. */
+		nprm->textValue = NULL;
 	}
 
 	return retval;
@@ -247,6 +251,9 @@ RestoreParamList(char **start_address)
 
 		/* Read datum/isnull. */
 		prm->value = datumRestore(start_address, &prm->isnull);
+
+		/* We don't copy text values, as no caller needs that at present. */
+		prm->textValue = NULL;
 	}
 
 	return paramLI;
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index e8d8e6f828..ec1e4092f5 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -86,6 +86,12 @@
  */
 const char *debug_query_string; /* client-supplied query string */
 
+/*
+ * The top-level portal that the client is immediately working with:
+ * creating, binding, executing, or all at one using simple protocol
+ */
+Portal current_top_portal = NULL;
+
 /* Note: whereToSendOutput is initialized for the bootstrap/standalone case */
 CommandDest whereToSendOutput = DestDebug;
 
@@ -1714,6 +1720,9 @@ exec_bind_message(StringInfo input_message)
 	else
 		portal = CreatePortal(portal_name, false, false);
 
+	Assert(current_top_portal == NULL);
+	current_top_portal = portal;
+
 	/*
 	 * Prepare to copy stuff into the portal's memory context.  We do all this
 	 * copying first, because it could possibly fail (out-of-memory) and we
@@ -1751,6 +1760,9 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* GUC value can change, so we remember its state to be consistent */
+		bool need_text_values = log_parameters_on_error;
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1818,9 +1830,18 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				/*
+				 * If we need the parameter string, keep it -- possibly making
+				 * a copy first, if necessary.  Otherwise get rid of it.
+				 */
+				if (pstring)
+				{
+					if (need_text_values)
+						params->params[paramno].textValue =
+							pstring == pbuf.data ? pstrdup(pstring) : pstring;
+					else if (pstring != pbuf.data)
+						pfree(pstring);
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1846,6 +1867,23 @@ exec_bind_message(StringInfo input_message)
 							(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
 							 errmsg("incorrect binary data format in bind parameter %d",
 									paramno + 1)));
+
+				/*
+				 * Compute textual representation for further logging.
+				 *
+				 * This could be optimized for certain built-in types, for
+				 * which the output function is safe to call even in an
+				 * aborted transaction.
+				 */
+				if (!isNull && need_text_values)
+				{
+					Oid			typoutput;
+					bool		typisvarlena;
+
+					getTypeOutputInfo(ptype, &typoutput, &typisvarlena);
+					params->params[paramno].textValue =
+						OidOutputFunctionCall(typoutput, pval);
+				}
 			}
 			else
 			{
@@ -1870,10 +1908,19 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/* Only now can we safely set this. */
+		params->hasTextValues = need_text_values;
 	}
 	else
 		params = NULL;
 
+	/*
+	 * Set portal parameters early for them to get logged if an error happens
+	 * on planning stage
+	 */
+	portal->portalParams = params;
+
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
@@ -1954,6 +2001,7 @@ exec_bind_message(StringInfo input_message)
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2004,32 +2052,49 @@ exec_execute_message(const char *portal_name, long max_rows)
 	/* Does the portal contain a transaction command? */
 	is_xact_command = IsTransactionStmtList(portal->stmts);
 
-	/*
-	 * We must copy the sourceText and prepStmtName into MessageContext in
-	 * case the portal is destroyed during finish_xact_command. Can avoid the
-	 * copy if it's not an xact command, though.
-	 */
 	if (is_xact_command)
 	{
+		/*
+		 * We must copy the sourceText and prepStmtName into MessageContext in
+		 * case the portal is destroyed during finish_xact_command.
+		 */
 		sourceText = pstrdup(portal->sourceText);
 		if (portal->prepStmtName)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
 		/*
 		 * An xact command shouldn't have any parameters, which is a good
 		 * thing because they wouldn't be around after finish_xact_command.
 		 */
 		portalParams = NULL;
+
+		/*
+		 * We don't set current top portal for xact cmds, as
+		 * 1) the portal may be destroyed earlier than the error happens
+		 * 2) it anyway has no parameters in it to log
+		 */
+		Assert(current_top_portal == NULL);
 	}
 	else
 	{
+		/*
+		 * The portal will remain there until we leave the function, so it's
+		 * safe avoid copying and just to refer to the data in its memory
+		 * context instead
+		 */
 		sourceText = portal->sourceText;
 		if (portal->prepStmtName)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
+
+		/*
+		 * For non-xact commands, we remember the current portal and its bind
+		 * parameters for further use in logging
+		 */
+		Assert(current_top_portal == NULL);
+		current_top_portal = portal;
 		portalParams = portal->portalParams;
 	}
 
@@ -2178,6 +2243,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2306,61 +2372,21 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
-	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
+	MemoryContext oldcontext;
+	char	   *params_message;
 
-		pfree(param_str.data);
+	/* Make sure any trash is generated in MessageContext */
+	oldcontext = MemoryContextSwitchTo(MessageContext);
+	params_message = get_portal_bind_params(params);
 
-		MemoryContextSwitchTo(oldcontext);
+	if (params_message)
+	{
+		errdetail("parameters: %s", params_message);
+		pfree(params_message);
 	}
 
+	MemoryContextSwitchTo(oldcontext);
+
 	return 0;
 }
 
@@ -2678,6 +2704,86 @@ drop_unnamed_stmt(void)
 	}
 }
 
+/*
+ * get_portal_bind_params
+ * 		Get a string containing parameters data -- used for logging.
+ *
+ * Can return NULL if there are no parameters in the portal or the portal is
+ * not valid, or the text representations of the parameters are not available.
+ * If returning a non-NULL value, it allocates memory for the returned string
+ * in the current context, and it's the caller's responsibility to pfree() it.
+ */
+char *
+get_portal_bind_params(ParamListInfo params)
+{
+	StringInfoData param_str;
+
+	/* No parameters to format */
+	if (!params || params->numParams == 0)
+		return NULL;
+
+	/*
+	 * We either need textual representation of parameters pre-calculated, or
+	 * call potentially user-defined I/O functions to convert the internal
+	 * representation into text, which cannot be done in an aborted xact
+	 */
+	if (!params->hasTextValues && IsAbortedTransactionBlockState())
+		return NULL;
+
+	initStringInfo(&param_str);
+
+	/* This code doesn't support dynamic param lists */
+	Assert(params->paramFetch == NULL);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *prm = &params->params[paramno];
+		char	   *pstring;
+		char	   *p;
+
+		appendStringInfo(&param_str, "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (prm->isnull)
+		{
+			appendStringInfoString(&param_str, "NULL");
+			continue;
+		}
+
+		if (params->hasTextValues)
+			pstring = prm->textValue;
+		else
+		{
+			Oid			typoutput;
+			bool		typisvarlena;
+
+			if (!OidIsValid(prm->ptype))
+			{
+				appendStringInfoString(&param_str, "UNKNOWN TYPE");
+				continue;
+			}
+
+			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
+			pstring = OidOutputFunctionCall(typoutput, prm->value);
+		}
+
+		appendStringInfoCharMacro(&param_str, '\'');
+		for (p = pstring; *p; p++)
+		{
+			if (*p == '\'') /* double single quotes */
+				appendStringInfoCharMacro(&param_str, *p);
+			appendStringInfoCharMacro(&param_str, *p);
+		}
+		appendStringInfoCharMacro(&param_str, '\'');
+
+		if (!params->hasTextValues)
+			pfree(pstring);
+	}
+
+	return param_str.data;
+}
+
 
 /* --------------------------------
  *		signal handler routines used in PostgresMain()
@@ -4031,10 +4137,11 @@ PostgresMain(int argc, char *argv[],
 		EmitErrorReport();
 
 		/*
-		 * Make sure debug_query_string gets reset before we possibly clobber
-		 * the storage it points at.
+		 * Make sure these get reset before we possibly clobber
+		 * the storages they point at.
 		 */
 		debug_query_string = NULL;
+		current_top_portal = NULL;
 
 		/*
 		 * Abort the current transaction in order to recover.
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 8b4720ef3a..40896a2d09 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -76,6 +76,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 #include "utils/ps_status.h"
 
 
@@ -344,6 +345,7 @@ errstart(int elevel, const char *filename, int lineno,
 		{
 			error_context_stack = NULL;
 			debug_query_string = NULL;
+			current_top_portal = NULL;
 		}
 	}
 	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
@@ -2788,6 +2790,19 @@ write_csvlog(ErrorData *edata)
 	if (print_stmt && edata->cursorpos > 0)
 		appendStringInfo(&buf, "%d", edata->cursorpos);
 	appendStringInfoChar(&buf, ',');
+	if (print_stmt && log_parameters_on_error &&
+		PortalIsValid(current_top_portal))
+	{
+		char *params;
+
+		params = get_portal_bind_params(current_top_portal->portalParams);
+		if (params != NULL)
+		{
+			appendCSVLiteral(&buf, params);
+			pfree(params);
+		}
+	}
+	appendStringInfoChar(&buf, ',');
 
 	/* file error location */
 	if (Log_error_verbosity >= PGERROR_VERBOSE)
@@ -2944,6 +2959,19 @@ send_message_to_server_log(ErrorData *edata)
 		appendStringInfoString(&buf, _("STATEMENT:  "));
 		append_with_tabs(&buf, debug_query_string);
 		appendStringInfoChar(&buf, '\n');
+
+		if (log_parameters_on_error && PortalIsValid(current_top_portal))
+		{
+			char *params;
+
+			params = get_portal_bind_params(current_top_portal->portalParams);
+			if (params != NULL)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("PARAMETERS:  %s\n"), params);
+				pfree(params);
+			}
+		}
 	}
 
 #ifdef HAVE_SYSLOG
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 2178e1cf5e..c034f88bfa 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -483,6 +483,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1293,6 +1294,15 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
+	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
 	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 0fc23e3a61..fccfff3a03 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -532,6 +532,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd9046619c..316d3a2888 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -93,6 +93,7 @@ typedef struct ParamExternData
 	bool		isnull;			/* is it NULL? */
 	uint16		pflags;			/* flag bits, see above */
 	Oid			ptype;			/* parameter's datatype, or 0 */
+	char	   *textValue;		/* textual representation for debug purposes */
 } ParamExternData;
 
 typedef struct ParamListInfoData *ParamListInfo;
@@ -116,6 +117,8 @@ typedef struct ParamListInfoData
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
 	int			numParams;		/* nominal/maximum # of Params represented */
+	bool		hasTextValues;	/* whether textValue for all non-null
+														params is populated */
 
 	/*
 	 * params[] may be of length zero if paramFetch is supplied; otherwise it
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index ec21f7e45c..ad6517414b 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -19,6 +19,7 @@
 #include "nodes/plannodes.h"
 #include "storage/procsignal.h"
 #include "utils/guc.h"
+#include "utils/portal.h"
 #include "utils/queryenvironment.h"
 
 
@@ -27,6 +28,8 @@
 
 extern CommandDest whereToSendOutput;
 extern PGDLLIMPORT const char *debug_query_string;
+extern PGDLLIMPORT Portal current_top_portal;
+
 extern int	max_stack_depth;
 extern int	PostAuthDelay;
 
@@ -78,6 +81,7 @@ extern long get_stack_depth_rlimit(void);
 extern void ResetUsage(void);
 extern void ShowUsage(const char *title);
 extern int	check_log_duration(char *msec_str, bool was_logged);
+extern char *get_portal_bind_params(ParamListInfo params);
 extern void set_debug_options(int debug_flag,
 							  GucContext context, GucSource source);
 extern bool set_plan_disabling_options(const char *arg,
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 6791e0cbc2..57acc28ef9 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
diff --git a/src/test/README b/src/test/README
index b5ccfc0cf6..22e624d8ba 100644
--- a/src/test/README
+++ b/src/test/README
@@ -12,8 +12,7 @@ authentication/
   Tests for authentication
 
 examples/
-  Demonstration programs for libpq that double as regression tests via
-  "make check"
+  Demonstration programs for libpq that double as regression tests
 
 isolation/
   Tests for concurrent behavior at the SQL level
diff --git a/src/test/examples/.gitignore b/src/test/examples/.gitignore
index 1957ec198f..007aaee590 100644
--- a/src/test/examples/.gitignore
+++ b/src/test/examples/.gitignore
@@ -2,5 +2,6 @@
 /testlibpq2
 /testlibpq3
 /testlibpq4
+/testlibpq5
 /testlo
 /testlo64
diff --git a/src/test/examples/Makefile b/src/test/examples/Makefile
index a67f456904..0407ca60bc 100644
--- a/src/test/examples/Makefile
+++ b/src/test/examples/Makefile
@@ -14,7 +14,7 @@ override CPPFLAGS := -I$(libpq_srcdir) $(CPPFLAGS)
 LDFLAGS_INTERNAL += $(libpq_pgport)
 
 
-PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlo testlo64
+PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlibpq5 testlo testlo64
 
 all: $(PROGS)
 
diff --git a/src/test/examples/testlibpq5.c b/src/test/examples/testlibpq5.c
index e69de29bb2..69b65c512b 100644
--- a/src/test/examples/testlibpq5.c
+++ b/src/test/examples/testlibpq5.c
@@ -0,0 +1,116 @@
+/*
+ * src/test/examples/testlibpq5.c
+ *
+ * testlibpq5.c
+ *		Test logging of statement parameters in case of errors.
+ */
+
+#ifdef WIN32
+#include <windows.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/types.h>
+#include "libpq-fe.h"
+
+static void
+exit_nicely(PGconn *conn)
+{
+	PQfinish(conn);
+	exit(1);
+}
+
+int
+main(int argc, char **argv)
+{
+	const char *conninfo;
+	PGconn	   *conn;
+	PGresult   *res;
+	const char *paramValues[3];
+	int			paramLengths[3];
+	int			paramFormats[3];
+	uint32_t	binaryIntVal;
+
+	/*
+	 * If the user supplies a parameter on the command line, use it as the
+	 * conninfo string; otherwise default to setting dbname=postgres and using
+	 * environment variables or defaults for all other connection parameters.
+	 */
+	if (argc > 1)
+		conninfo = argv[1];
+	else
+		conninfo = "dbname = postgres";
+
+	/* Make a connection to the database */
+	conn = PQconnectdb(conninfo);
+
+	/* Check to see that the backend connection was successfully made */
+	if (PQstatus(conn) != CONNECTION_OK)
+	{
+		fprintf(stderr, "Connection to database failed: %s",
+				PQerrorMessage(conn));
+		exit_nicely(conn);
+	}
+
+	/* Set always-secure search path, so malicious users can't take control. */
+	res = PQexec(conn,
+				 "SELECT pg_catalog.set_config('search_path', '', false)");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/*
+	 * Transmit parameters in different forms and make a statement fail.  User
+	 * can then verify the server log.
+	 */
+	res = PQexec(conn, "SET log_parameters_on_error = on");
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	paramValues[0] = (char *) &binaryIntVal;
+	paramLengths[0] = sizeof(binaryIntVal);
+	paramFormats[0] = 1;		/* binary */
+	paramValues[1] = "2";
+	paramLengths[1] = strlen(paramValues[1]) + 1;
+	paramFormats[1] = 0;		/* text */
+	paramValues[2] = (char *) "everyone's little $$ in \"dollar\"";
+	paramLengths[2] = strlen(paramValues[2]) + 1;
+	paramFormats[2] = 0;		/* text */
+	/* divide by zero -- but server won't realize until execution */
+	res = PQexecParams(conn,
+					   "SELECT 1 / (random() / 2)::int + $1::int + $2::int, $3::text",
+					   3,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero expected, got an error message from server: %s\n"
+		   "Please make sure it has been logged with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* close the connection to the database and cleanup */
+	PQfinish(conn);
+
+	return 0;
+}

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 0191ec84b1..832ebe57a3 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6492,6 +6492,29 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether bind parameters are logged when a statement is logged
+        as a result of <xref linkend="guc-log-min-error-statement"/>.
+        It adds some overhead, as postgres will compute and store textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged.
+        This setting has no effect on statements logged due to
+        <xref linkend="guc-log-min-duration-statement"/> or
+        <xref linkend="guc-log-statement"/> settings, as they are always logged
+        with parameters.
+        The default is <literal>off</literal>.
+        Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 7e0a041fab..7692ea551b 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -406,7 +406,7 @@ EvaluateParams(PreparedStatement *pstmt, List *params,
 		prm->value = ExecEvalExprSwitchContext(n,
 											   GetPerTupleExprContext(estate),
 											   &prm->isnull);
-
+		prm->textValue = NULL;
 		i++;
 	}
 
diff --git a/src/backend/executor/functions.c b/src/backend/executor/functions.c
index 83337c2eed..92fcee8b19 100644
--- a/src/backend/executor/functions.c
+++ b/src/backend/executor/functions.c
@@ -925,6 +925,7 @@ postquel_sub_params(SQLFunctionCachePtr fcache,
 			prm->isnull = fcinfo->args[i].isnull;
 			prm->pflags = 0;
 			prm->ptype = fcache->pinfo->argtypes[i];
+			prm->textValue = NULL;
 		}
 	}
 	else
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 2c0ae395ba..f6b4246b47 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -2458,6 +2458,7 @@ _SPI_convert_params(int nargs, Oid *argtypes,
 			prm->isnull = (Nulls && Nulls[i] == 'n');
 			prm->pflags = PARAM_FLAG_CONST;
 			prm->ptype = argtypes[i];
+			prm->textValue = NULL;
 		}
 	}
 	else
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index cf4387e40f..bf8e3705af 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -45,6 +45,7 @@ makeParamList(int numParams)
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
 	retval->numParams = numParams;
+	retval->hasTextValues = false;
 
 	return retval;
 }
@@ -91,6 +92,9 @@ copyParamList(ParamListInfo from)
 			continue;
 		get_typlenbyval(nprm->ptype, &typLen, &typByVal);
 		nprm->value = datumCopy(nprm->value, typByVal, typLen);
+
+		/* We don't copy text values, as no caller needs that at present. */
+		nprm->textValue = NULL;
 	}
 
 	return retval;
@@ -247,6 +251,9 @@ RestoreParamList(char **start_address)
 
 		/* Read datum/isnull. */
 		prm->value = datumRestore(start_address, &prm->isnull);
+
+		/* We don't copy text values, as no caller needs that at present. */
+		prm->textValue = NULL;
 	}
 
 	return paramLI;
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 4bec40aa28..4b648a9f0a 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -86,6 +86,12 @@
  */
 const char *debug_query_string; /* client-supplied query string */
 
+/*
+ * The top-level portal that the client is immediately working with:
+ * creating, binding, executing, or all at one using simple protocol
+ */
+Portal current_top_portal = NULL;
+
 /* Note: whereToSendOutput is initialized for the bootstrap/standalone case */
 CommandDest whereToSendOutput = DestDebug;
 
@@ -1716,6 +1722,9 @@ exec_bind_message(StringInfo input_message)
 	else
 		portal = CreatePortal(portal_name, false, false);
 
+	Assert(current_top_portal == NULL);
+	current_top_portal = portal;
+
 	/*
 	 * Prepare to copy stuff into the portal's memory context.  We do all this
 	 * copying first, because it could possibly fail (out-of-memory) and we
@@ -1753,6 +1762,9 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* GUC value can change, so we remember its state to be consistent */
+		bool need_text_values = log_parameters_on_error;
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1820,9 +1832,18 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				/*
+				 * If we need the parameter string, keep it -- possibly making
+				 * a copy first, if necessary.  Otherwise get rid of it.
+				 */
+				if (pstring)
+				{
+					if (need_text_values)
+						params->params[paramno].textValue =
+							pstring == pbuf.data ? pstrdup(pstring) : pstring;
+					else if (pstring != pbuf.data)
+						pfree(pstring);
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1848,6 +1869,23 @@ exec_bind_message(StringInfo input_message)
 							(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
 							 errmsg("incorrect binary data format in bind parameter %d",
 									paramno + 1)));
+
+				/*
+				 * Compute textual representation for further logging.
+				 *
+				 * This could be optimized for certain built-in types, for
+				 * which the output function is safe to call even in an
+				 * aborted transaction.
+				 */
+				if (!isNull && need_text_values)
+				{
+					Oid			typoutput;
+					bool		typisvarlena;
+
+					getTypeOutputInfo(ptype, &typoutput, &typisvarlena);
+					params->params[paramno].textValue =
+						OidOutputFunctionCall(typoutput, pval);
+				}
 			}
 			else
 			{
@@ -1872,10 +1910,19 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/* Only now can we safely set this. */
+		params->hasTextValues = need_text_values;
 	}
 	else
 		params = NULL;
 
+	/*
+	 * Set portal parameters early for them to get logged if an error happens
+	 * on planning stage
+	 */
+	portal->portalParams = params;
+
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
@@ -1956,6 +2003,7 @@ exec_bind_message(StringInfo input_message)
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2006,32 +2054,49 @@ exec_execute_message(const char *portal_name, long max_rows)
 	/* Does the portal contain a transaction command? */
 	is_xact_command = IsTransactionStmtList(portal->stmts);
 
-	/*
-	 * We must copy the sourceText and prepStmtName into MessageContext in
-	 * case the portal is destroyed during finish_xact_command. Can avoid the
-	 * copy if it's not an xact command, though.
-	 */
 	if (is_xact_command)
 	{
+		/*
+		 * We must copy the sourceText and prepStmtName into MessageContext in
+		 * case the portal is destroyed during finish_xact_command.
+		 */
 		sourceText = pstrdup(portal->sourceText);
 		if (portal->prepStmtName)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
 		/*
 		 * An xact command shouldn't have any parameters, which is a good
 		 * thing because they wouldn't be around after finish_xact_command.
 		 */
 		portalParams = NULL;
+
+		/*
+		 * We don't set current top portal for xact cmds, as
+		 * 1) the portal may be destroyed earlier than the error happens
+		 * 2) it anyway has no parameters in it to log
+		 */
+		Assert(current_top_portal == NULL);
 	}
 	else
 	{
+		/*
+		 * The portal will remain there until we leave the function, so it's
+		 * safe avoid copying and just to refer to the data in its memory
+		 * context instead
+		 */
 		sourceText = portal->sourceText;
 		if (portal->prepStmtName)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
+
+		/*
+		 * For non-xact commands, we remember the current portal and its bind
+		 * parameters for further use in logging
+		 */
+		Assert(current_top_portal == NULL);
+		current_top_portal = portal;
 		portalParams = portal->portalParams;
 	}
 
@@ -2183,6 +2248,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	current_top_portal = NULL;
 	debug_query_string = NULL;
 }
 
@@ -2311,61 +2377,21 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
-	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
+	MemoryContext oldcontext;
+	char	   *params_message;
 
-		pfree(param_str.data);
+	/* Make sure any trash is generated in MessageContext */
+	oldcontext = MemoryContextSwitchTo(MessageContext);
+	params_message = get_portal_bind_params(params);
 
-		MemoryContextSwitchTo(oldcontext);
+	if (params_message)
+	{
+		errdetail("parameters: %s", params_message);
+		pfree(params_message);
 	}
 
+	MemoryContextSwitchTo(oldcontext);
+
 	return 0;
 }
 
@@ -2683,6 +2709,86 @@ drop_unnamed_stmt(void)
 	}
 }
 
+/*
+ * get_portal_bind_params
+ * 		Get a string containing parameters data -- used for logging.
+ *
+ * Can return NULL if there are no parameters in the portal or the portal is
+ * not valid, or the text representations of the parameters are not available.
+ * If returning a non-NULL value, it allocates memory for the returned string
+ * in the current context, and it's the caller's responsibility to pfree() it.
+ */
+char *
+get_portal_bind_params(ParamListInfo params)
+{
+	StringInfoData param_str;
+
+	/* No parameters to format */
+	if (!params || params->numParams == 0)
+		return NULL;
+
+	/*
+	 * We either need textual representation of parameters pre-calculated, or
+	 * call potentially user-defined I/O functions to convert the internal
+	 * representation into text, which cannot be done in an aborted xact
+	 */
+	if (!params->hasTextValues && IsAbortedTransactionBlockState())
+		return NULL;
+
+	initStringInfo(&param_str);
+
+	/* This code doesn't support dynamic param lists */
+	Assert(params->paramFetch == NULL);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *prm = &params->params[paramno];
+		char	   *pstring;
+		char	   *p;
+
+		appendStringInfo(&param_str, "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (prm->isnull)
+		{
+			appendStringInfoString(&param_str, "NULL");
+			continue;
+		}
+
+		if (params->hasTextValues)
+			pstring = prm->textValue;
+		else
+		{
+			Oid			typoutput;
+			bool		typisvarlena;
+
+			if (!OidIsValid(prm->ptype))
+			{
+				appendStringInfoString(&param_str, "UNKNOWN TYPE");
+				continue;
+			}
+
+			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
+			pstring = OidOutputFunctionCall(typoutput, prm->value);
+		}
+
+		appendStringInfoCharMacro(&param_str, '\'');
+		for (p = pstring; *p; p++)
+		{
+			if (*p == '\'') /* double single quotes */
+				appendStringInfoCharMacro(&param_str, *p);
+			appendStringInfoCharMacro(&param_str, *p);
+		}
+		appendStringInfoCharMacro(&param_str, '\'');
+
+		if (!params->hasTextValues)
+			pfree(pstring);
+	}
+
+	return param_str.data;
+}
+
 
 /* --------------------------------
  *		signal handler routines used in PostgresMain()
@@ -4035,10 +4141,11 @@ PostgresMain(int argc, char *argv[],
 		EmitErrorReport();
 
 		/*
-		 * Make sure debug_query_string gets reset before we possibly clobber
-		 * the storage it points at.
+		 * Make sure these get reset before we possibly clobber
+		 * the storages they point at.
 		 */
 		debug_query_string = NULL;
+		current_top_portal = NULL;
 
 		/*
 		 * Abort the current transaction in order to recover.
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index 8b4720ef3a..40896a2d09 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -76,6 +76,7 @@
 #include "tcop/tcopprot.h"
 #include "utils/guc.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 #include "utils/ps_status.h"
 
 
@@ -344,6 +345,7 @@ errstart(int elevel, const char *filename, int lineno,
 		{
 			error_context_stack = NULL;
 			debug_query_string = NULL;
+			current_top_portal = NULL;
 		}
 	}
 	if (++errordata_stack_depth >= ERRORDATA_STACK_SIZE)
@@ -2788,6 +2790,19 @@ write_csvlog(ErrorData *edata)
 	if (print_stmt && edata->cursorpos > 0)
 		appendStringInfo(&buf, "%d", edata->cursorpos);
 	appendStringInfoChar(&buf, ',');
+	if (print_stmt && log_parameters_on_error &&
+		PortalIsValid(current_top_portal))
+	{
+		char *params;
+
+		params = get_portal_bind_params(current_top_portal->portalParams);
+		if (params != NULL)
+		{
+			appendCSVLiteral(&buf, params);
+			pfree(params);
+		}
+	}
+	appendStringInfoChar(&buf, ',');
 
 	/* file error location */
 	if (Log_error_verbosity >= PGERROR_VERBOSE)
@@ -2944,6 +2959,19 @@ send_message_to_server_log(ErrorData *edata)
 		appendStringInfoString(&buf, _("STATEMENT:  "));
 		append_with_tabs(&buf, debug_query_string);
 		appendStringInfoChar(&buf, '\n');
+
+		if (log_parameters_on_error && PortalIsValid(current_top_portal))
+		{
+			char *params;
+
+			params = get_portal_bind_params(current_top_portal->portalParams);
+			if (params != NULL)
+			{
+				log_line_prefix(&buf, edata);
+				appendStringInfo(&buf, _("PARAMETERS:  %s\n"), params);
+				pfree(params);
+			}
+		}
 	}
 
 #ifdef HAVE_SYSLOG
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 31a5ef0474..9ccd2c2bf0 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -483,6 +483,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1293,6 +1294,15 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
+	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
 	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 0fc23e3a61..fccfff3a03 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -532,6 +532,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd9046619c..316d3a2888 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -93,6 +93,7 @@ typedef struct ParamExternData
 	bool		isnull;			/* is it NULL? */
 	uint16		pflags;			/* flag bits, see above */
 	Oid			ptype;			/* parameter's datatype, or 0 */
+	char	   *textValue;		/* textual representation for debug purposes */
 } ParamExternData;
 
 typedef struct ParamListInfoData *ParamListInfo;
@@ -116,6 +117,8 @@ typedef struct ParamListInfoData
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
 	int			numParams;		/* nominal/maximum # of Params represented */
+	bool		hasTextValues;	/* whether textValue for all non-null
+														params is populated */
 
 	/*
 	 * params[] may be of length zero if paramFetch is supplied; otherwise it
diff --git a/src/include/tcop/tcopprot.h b/src/include/tcop/tcopprot.h
index ec21f7e45c..ad6517414b 100644
--- a/src/include/tcop/tcopprot.h
+++ b/src/include/tcop/tcopprot.h
@@ -19,6 +19,7 @@
 #include "nodes/plannodes.h"
 #include "storage/procsignal.h"
 #include "utils/guc.h"
+#include "utils/portal.h"
 #include "utils/queryenvironment.h"
 
 
@@ -27,6 +28,8 @@
 
 extern CommandDest whereToSendOutput;
 extern PGDLLIMPORT const char *debug_query_string;
+extern PGDLLIMPORT Portal current_top_portal;
+
 extern int	max_stack_depth;
 extern int	PostAuthDelay;
 
@@ -78,6 +81,7 @@ extern long get_stack_depth_rlimit(void);
 extern void ResetUsage(void);
 extern void ShowUsage(const char *title);
 extern int	check_log_duration(char *msec_str, bool was_logged);
+extern char *get_portal_bind_params(ParamListInfo params);
 extern void set_debug_options(int debug_flag,
 							  GucContext context, GucSource source);
 extern bool set_plan_disabling_options(const char *arg,
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 6791e0cbc2..57acc28ef9 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
diff --git a/src/test/README b/src/test/README
index b5ccfc0cf6..22e624d8ba 100644
--- a/src/test/README
+++ b/src/test/README
@@ -12,8 +12,7 @@ authentication/
   Tests for authentication
 
 examples/
-  Demonstration programs for libpq that double as regression tests via
-  "make check"
+  Demonstration programs for libpq that double as regression tests
 
 isolation/
   Tests for concurrent behavior at the SQL level
diff --git a/src/test/examples/.gitignore b/src/test/examples/.gitignore
index 1957ec198f..007aaee590 100644
--- a/src/test/examples/.gitignore
+++ b/src/test/examples/.gitignore
@@ -2,5 +2,6 @@
 /testlibpq2
 /testlibpq3
 /testlibpq4
+/testlibpq5
 /testlo
 /testlo64
diff --git a/src/test/examples/Makefile b/src/test/examples/Makefile
index a67f456904..0407ca60bc 100644
--- a/src/test/examples/Makefile
+++ b/src/test/examples/Makefile
@@ -14,7 +14,7 @@ override CPPFLAGS := -I$(libpq_srcdir) $(CPPFLAGS)
 LDFLAGS_INTERNAL += $(libpq_pgport)
 
 
-PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlo testlo64
+PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlibpq5 testlo testlo64
 
 all: $(PROGS)
 
diff --git a/src/test/examples/testlibpq5.c b/src/test/examples/testlibpq5.c
new file mode 100644
index 0000000000..69b65c512b
--- /dev/null
+++ b/src/test/examples/testlibpq5.c
@@ -0,0 +1,116 @@
+/*
+ * src/test/examples/testlibpq5.c
+ *
+ * testlibpq5.c
+ *		Test logging of statement parameters in case of errors.
+ */
+
+#ifdef WIN32
+#include <windows.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/types.h>
+#include "libpq-fe.h"
+
+static void
+exit_nicely(PGconn *conn)
+{
+	PQfinish(conn);
+	exit(1);
+}
+
+int
+main(int argc, char **argv)
+{
+	const char *conninfo;
+	PGconn	   *conn;
+	PGresult   *res;
+	const char *paramValues[3];
+	int			paramLengths[3];
+	int			paramFormats[3];
+	uint32_t	binaryIntVal;
+
+	/*
+	 * If the user supplies a parameter on the command line, use it as the
+	 * conninfo string; otherwise default to setting dbname=postgres and using
+	 * environment variables or defaults for all other connection parameters.
+	 */
+	if (argc > 1)
+		conninfo = argv[1];
+	else
+		conninfo = "dbname = postgres";
+
+	/* Make a connection to the database */
+	conn = PQconnectdb(conninfo);
+
+	/* Check to see that the backend connection was successfully made */
+	if (PQstatus(conn) != CONNECTION_OK)
+	{
+		fprintf(stderr, "Connection to database failed: %s",
+				PQerrorMessage(conn));
+		exit_nicely(conn);
+	}
+
+	/* Set always-secure search path, so malicious users can't take control. */
+	res = PQexec(conn,
+				 "SELECT pg_catalog.set_config('search_path', '', false)");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/*
+	 * Transmit parameters in different forms and make a statement fail.  User
+	 * can then verify the server log.
+	 */
+	res = PQexec(conn, "SET log_parameters_on_error = on");
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	paramValues[0] = (char *) &binaryIntVal;
+	paramLengths[0] = sizeof(binaryIntVal);
+	paramFormats[0] = 1;		/* binary */
+	paramValues[1] = "2";
+	paramLengths[1] = strlen(paramValues[1]) + 1;
+	paramFormats[1] = 0;		/* text */
+	paramValues[2] = (char *) "everyone's little $$ in \"dollar\"";
+	paramLengths[2] = strlen(paramValues[2]) + 1;
+	paramFormats[2] = 0;		/* text */
+	/* divide by zero -- but server won't realize until execution */
+	res = PQexecParams(conn,
+					   "SELECT 1 / (random() / 2)::int + $1::int + $2::int, $3::text",
+					   3,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero expected, got an error message from server: %s\n"
+		   "Please make sure it has been logged with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* close the connection to the database and cleanup */
+	PQfinish(conn);
+
+	return 0;
+}

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 4ec13f3311..b3a0d27861 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6597,6 +6597,29 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether bind parameters are logged when a statement is logged
+        as a result of <xref linkend="guc-log-min-error-statement"/>.
+        It adds some overhead, as postgres will compute and store textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged.
+        This setting has no effect on statements logged due to
+        <xref linkend="guc-log-min-duration-statement"/> or
+        <xref linkend="guc-log-statement"/> settings, as they are always logged
+        with parameters.
+        The default is <literal>off</literal>.
+        Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index cf4387e40f..7c1f86f5c5 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -15,12 +15,16 @@
 
 #include "postgres.h"
 
+#include "lib/stringinfo.h"
 #include "nodes/bitmapset.h"
 #include "nodes/params.h"
 #include "storage/shmem.h"
 #include "utils/datum.h"
+#include "utils/guc.h"
 #include "utils/lsyscache.h"
+#include "utils/memutils.h"
 
+static void LogParams(void *arg);
 
 /*
  * Allocate and initialize a new ParamListInfo structure.
@@ -44,6 +48,7 @@ makeParamList(int numParams)
 	retval->paramCompileArg = NULL;
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
+	retval->logString = NULL;
 	retval->numParams = numParams;
 
 	return retval;
@@ -58,6 +63,8 @@ makeParamList(int numParams)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * We also don't copy logString.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -221,6 +228,8 @@ SerializeParamList(ParamListInfo paramLI, char **start_address)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * We also don't copy logString.
  */
 ParamListInfo
 RestoreParamList(char **start_address)
@@ -251,3 +260,152 @@ RestoreParamList(char **start_address)
 
 	return paramLI;
 }
+
+/*
+ * BuildParamLogString - create a string to represent parameters list for
+ * logging and save it to params. If caller already knows textual
+ * representations for some or all parameters, it can pass an array of exactly
+ * params->numParams values as knownTextValues. It can contain NULLs for the
+ * individual values not known, or, if no text text values known at all the
+ * caller may pass NULL pointer.
+ */
+void
+BuildParamLogString(ParamListInfo params, char **knownTextValues)
+{
+	MemoryContext tmpCxt,
+				  oldCxt;
+	int logStringLen = 0;
+	StringInfoData logString;
+	char **textValues;
+
+	if (params->logString != NULL)
+		return;
+
+	Assert(params->paramFetch == NULL);
+
+	initStringInfo(&logString);
+
+	tmpCxt = AllocSetContextCreate(CurrentMemoryContext,
+								   "BuildParamLogString",
+								   ALLOCSET_DEFAULT_SIZES);
+	oldCxt = MemoryContextSwitchTo(tmpCxt);
+
+	textValues = (char **) palloc0(params->numParams * sizeof(char *));
+
+	/* calculate unknown text representations and pre-calculate byte lengths */
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData param = params->params[paramno];
+
+		/* reserve the space for the number of digits in paramno + 1 */
+		for (int d = paramno + 1; d > 0; d /= 10)
+			logStringLen++;
+
+		if (param.isnull)
+		{
+			logStringLen += 4; /* for "NULL" */
+		}
+		else
+		{
+			char *textValue,
+				 *s;
+
+			/* find out textValues[paramno] */
+			if (knownTextValues != NULL && knownTextValues[paramno] != NULL)
+			{
+				textValues[paramno] = knownTextValues[paramno];
+			}
+			else
+			{
+				Oid		typoutput;
+				bool	typisvarlena;
+				getTypeOutputInfo(param.ptype, &typoutput, &typisvarlena);
+				textValues[paramno] =
+								OidOutputFunctionCall(typoutput, param.value);
+			}
+
+			/* caluclate the space needed its printed length */
+			textValue = textValues[paramno];
+			for (s = textValue; *s != '\0'; s++)
+				if (*s == '\'')
+					logStringLen++; /* for quotes doubling */
+			/* string length + 2 for quotes */
+			logStringLen += s - textValue + 2;
+		}
+	}
+
+	/*
+	 * "$1 = something, " -- 6 bytes extra to the ordinal and the value;
+	 *  ^ ^^^         ^^
+	 * for the last one we don't need the comma and the space but need 0 byte
+	 */
+	logStringLen += params->numParams * 6 - 1;
+
+	MemoryContextSwitchTo(oldCxt);
+
+	/* enlarge at once to avoid multiple reallocations */
+	enlargeStringInfo(&logString, logStringLen);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		appendStringInfo(&logString,
+						 "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+		appendStringInfoStringQuoted(&logString, textValues[paramno]);
+	}
+
+	params->logString = logString.data;
+
+	MemoryContextDelete(tmpCxt);
+}
+
+/*
+ * PutParamsInErrorContext - if needed and possible,
+ * add an error context entry with bind parameters
+ *
+ * params is a pointer to ParamListInfo for the caller to be able to clear it
+ * if the actual ParamListInfo is gone
+ */
+void
+PutParamsInErrorContext(ErrorContextCallback *new_error_context_entry,
+						ParamListInfo *params)
+{
+	/*
+	 * Setting this anyway for the caller to be able to revert this operation
+	 * with `error_context_stack = new_error_context_entry->previous` regardless
+	 * whether we actually change the stack
+	 */
+	new_error_context_entry->previous = error_context_stack;
+
+	if (!log_parameters_on_error || *params == NULL
+								 || (*params)->logString == NULL)
+		return;
+
+	new_error_context_entry->callback = LogParams;
+	new_error_context_entry->arg = (void *)(params);
+	error_context_stack = new_error_context_entry;
+}
+
+/*
+ * LogParams - callback for printing parameters in error context
+ */
+static void
+LogParams(void *arg)
+{
+	ParamListInfo params = *((ParamListInfo *)(arg));
+
+	/*
+	 * XXX: errdetail_log copies the error message formatting, so we're
+	 * allocating a potentially large amounts of memory for the whole parameter
+	 * string again
+	 *
+	 * We can have NULL in params->logString if log_parameters_on_error was off
+	 * when we decided whether to call BuildParamLogString. In this rare case
+	 * we don't log the parameters: building the log string now wouldn't be safe
+	 * as we must't call user-defined I/O functions when in an aborted xact.
+	 */
+	if (params != NULL && params->logString != NULL
+							&& log_parameters_on_error && geterrshowstmt())
+		errdetail_log("parameters: %s", params->logString);
+}
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3b85e48333..9b562f7f01 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -177,7 +177,7 @@ static void forbidden_in_wal_sender(char firstchar);
 static List *pg_rewrite_query(Query *query);
 static bool check_log_statement(List *stmt_list);
 static int	errdetail_execute(List *raw_parsetree_list);
-static int	errdetail_params(ParamListInfo params);
+static int	errdetail_portal_params(Portal portal);
 static int	errdetail_abort(void);
 static int	errdetail_recovery_conflict(void);
 static void start_xact_command(void);
@@ -1596,23 +1596,24 @@ exec_parse_message(const char *query_string,	/* string to execute */
 static void
 exec_bind_message(StringInfo input_message)
 {
-	const char *portal_name;
-	const char *stmt_name;
-	int			numPFormats;
-	int16	   *pformats = NULL;
-	int			numParams;
-	int			numRFormats;
-	int16	   *rformats = NULL;
-	CachedPlanSource *psrc;
-	CachedPlan *cplan;
-	Portal		portal;
-	char	   *query_string;
-	char	   *saved_stmt_name;
-	ParamListInfo params;
-	MemoryContext oldContext;
-	bool		save_log_statement_stats = log_statement_stats;
-	bool		snapshot_set = false;
-	char		msec_str[32];
+	const char			*portal_name;
+	const char			*stmt_name;
+	int					 numPFormats;
+	int16				*pformats = NULL;
+	int					 numParams;
+	int					 numRFormats;
+	int16				*rformats = NULL;
+	CachedPlanSource	*psrc;
+	CachedPlan			*cplan;
+	Portal				 portal;
+	char				*query_string;
+	char				*saved_stmt_name;
+	ParamListInfo 		 params;
+	MemoryContext 		 oldContext;
+	bool				 save_log_statement_stats = log_statement_stats;
+	bool				 snapshot_set = false;
+	char				 msec_str[32];
+	ErrorContextCallback params_error_context;
 
 	/* Get the fixed part of the message */
 	portal_name = pq_getmsgstring(input_message);
@@ -1752,6 +1753,10 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* These are short-living, so we don't pollute the portal context */
+		char **knownTextValues = MemoryContextAllocZero(MessageContext,
+													numParams * sizeof(char *));
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1819,9 +1824,17 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				/*
+				 * If we need the parameter string, save it.
+				 * If not -- get rid of it.
+				 */
+				if (pstring)
+				{
+					if (log_parameters_on_error)
+						knownTextValues[paramno] = pstring;
+					else if (pstring != pbuf.data)
+						pfree(pstring);
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1871,6 +1884,9 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		if (log_parameters_on_error)
+			BuildParamLogString(params, knownTextValues);
 	}
 	else
 		params = NULL;
@@ -1878,6 +1894,9 @@ exec_bind_message(StringInfo input_message)
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
+	/* From now on, log parameters on error if enabled in GUC */
+	PutParamsInErrorContext(&params_error_context, &params);
+
 	/* Get the result format codes */
 	numRFormats = pq_getmsgint(input_message, 2);
 	if (numRFormats > 0)
@@ -1948,13 +1967,14 @@ exec_bind_message(StringInfo input_message)
 							*portal_name ? portal_name : "",
 							psrc->query_string),
 					 errhidestmt(true),
-					 errdetail_params(params)));
+					 errdetail_portal_params(portal)));
 			break;
 	}
 
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	error_context_stack = params_error_context.previous;
 	debug_query_string = NULL;
 }
 
@@ -1966,19 +1986,20 @@ exec_bind_message(StringInfo input_message)
 static void
 exec_execute_message(const char *portal_name, long max_rows)
 {
-	CommandDest dest;
-	DestReceiver *receiver;
-	Portal		portal;
-	bool		completed;
-	char		completionTag[COMPLETION_TAG_BUFSIZE];
-	const char *sourceText;
-	const char *prepStmtName;
-	ParamListInfo portalParams;
-	bool		save_log_statement_stats = log_statement_stats;
-	bool		is_xact_command;
-	bool		execute_is_fetch;
-	bool		was_logged = false;
-	char		msec_str[32];
+	CommandDest			 dest;
+	DestReceiver		 *receiver;
+	Portal				 portal;
+	ParamListInfo		 params;
+	bool				 completed;
+	char				 completionTag[COMPLETION_TAG_BUFSIZE];
+	const char			*sourceText;
+	const char			*prepStmtName;
+	bool				 save_log_statement_stats = log_statement_stats;
+	bool				 is_xact_command;
+	bool				 execute_is_fetch;
+	bool				 was_logged = false;
+	char				 msec_str[32];
+	ErrorContextCallback params_error_context;
 
 	/* Adjust destination to tell printtup.c what to do */
 	dest = whereToSendOutput;
@@ -2002,6 +2023,10 @@ exec_execute_message(const char *portal_name, long max_rows)
 		return;
 	}
 
+	/* From now on, log parameters on error if enabled in GUC */
+	params = portal->portalParams;
+	PutParamsInErrorContext(&params_error_context, &params);
+
 	/* Does the portal contain a transaction command? */
 	is_xact_command = IsTransactionStmtList(portal->stmts);
 
@@ -2017,12 +2042,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
-		/*
-		 * An xact command shouldn't have any parameters, which is a good
-		 * thing because they wouldn't be around after finish_xact_command.
-		 */
-		portalParams = NULL;
 	}
 	else
 	{
@@ -2031,7 +2050,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
-		portalParams = portal->portalParams;
 	}
 
 	/*
@@ -2083,7 +2101,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 						*portal_name ? portal_name : "",
 						sourceText),
 				 errhidestmt(true),
-				 errdetail_params(portalParams)));
+				 errdetail_portal_params(portal)));
 		was_logged = true;
 	}
 
@@ -2122,6 +2140,15 @@ exec_execute_message(const char *portal_name, long max_rows)
 	{
 		if (is_xact_command)
 		{
+			/*
+			 * The portal and its params may be destroyed during
+			 * finish_xact_command below. We only may need the portal for
+			 * parameters logging, but an xact command shouldn't have any
+			 * parameters.
+			 */
+			portal = NULL;
+			params = NULL;
+
 			/*
 			 * If this was a transaction control statement, commit it.  We
 			 * will start a new xact command for the next command (if any).
@@ -2175,13 +2202,14 @@ exec_execute_message(const char *portal_name, long max_rows)
 							*portal_name ? portal_name : "",
 							sourceText),
 					 errhidestmt(true),
-					 errdetail_params(portalParams)));
+					 errdetail_portal_params(portal)));
 			break;
 	}
 
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	error_context_stack = params_error_context.previous;
 	debug_query_string = NULL;
 }
 
@@ -2321,66 +2349,26 @@ errdetail_execute(List *raw_parsetree_list)
 }
 
 /*
- * errdetail_params
+ * errdetail_portal_params
  *
  * Add an errdetail() line showing bind-parameter data, if available.
  */
 static int
-errdetail_params(ParamListInfo params)
+errdetail_portal_params(Portal portal)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
+	if (portal != NULL &&
+		portal->portalParams &&
+		portal->portalParams->numParams > 0)
 	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
-
-		pfree(param_str.data);
+		/*
+		 * We switch back to portal context for the params logString to be
+		 * generated there in order to reuse it in later invocations
+		 */
+		MemoryContext old_cxt = MemoryContextSwitchTo(portal->portalContext);
+		BuildParamLogString(portal->portalParams, NULL);
+		MemoryContextSwitchTo(old_cxt);
 
-		MemoryContextSwitchTo(oldcontext);
+		errdetail("parameters: %s", portal->portalParams->logString);
 	}
 
 	return 0;
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index f46653632e..eb39c750f4 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -1363,6 +1363,22 @@ getinternalerrposition(void)
 	return edata->internalpos;
 }
 
+/*
+ * geterrshowstmt --- return whether we are going to print the statement in the log
+ *
+ * This is only intended for use in error callback subroutines, since there
+ * is no other place outside elog.c where the concept is meaningful.
+ */
+bool
+geterrshowstmt(void)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	return is_log_level_output(edata->elevel, log_min_error_statement) &&
+		debug_query_string != NULL &&
+		!edata->hide_stmt;
+}
+
 
 /*
  * elog_start --- startup for old-style API
@@ -2742,7 +2758,7 @@ static void
 write_csvlog(ErrorData *edata)
 {
 	StringInfoData buf;
-	bool		print_stmt = false;
+	bool print_stmt = geterrshowstmt();
 
 	/* static counter for line numbers */
 	static long log_line_number = 0;
@@ -2886,10 +2902,6 @@ write_csvlog(ErrorData *edata)
 	appendStringInfoChar(&buf, ',');
 
 	/* user query --- only reported if not disabled by the caller */
-	if (is_log_level_output(edata->elevel, log_min_error_statement) &&
-		debug_query_string != NULL &&
-		!edata->hide_stmt)
-		print_stmt = true;
 	if (print_stmt)
 		appendCSVLiteral(&buf, debug_query_string);
 	appendStringInfoChar(&buf, ',');
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 5fccc9683e..1be1f1fb29 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -486,6 +486,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1300,6 +1301,15 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
+	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
 	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 46a06ffacd..91cdc06fc4 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -544,6 +544,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
index a50e587da9..300fa4527b 100644
--- a/src/common/stringinfo.c
+++ b/src/common/stringinfo.c
@@ -178,6 +178,42 @@ appendStringInfoString(StringInfo str, const char *s)
 	appendBinaryStringInfo(str, s, strlen(s));
 }
 
+/*
+ * appendStringInfoStringQuoted
+ *
+ * Append a null-terminated string to str, adding single quotes around
+ * and doubling all single quotes.
+ */
+void
+appendStringInfoStringQuoted(StringInfo str, const char *s)
+{
+	const char *chunk_search_start = s,
+			   *chunk_copy_start = s,
+			   *chunk_end;
+
+	Assert(str != NULL);
+
+	appendStringInfoCharMacro(str, '\'');
+
+	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
+	{
+		/* copy including the found delimiting ' */
+		appendBinaryStringInfoNT(str,
+								 chunk_copy_start,
+								 chunk_end - chunk_copy_start + 1);
+
+		/* in order to double it, include this ' into the next chunk as well*/
+		chunk_copy_start = chunk_end;
+		chunk_search_start = chunk_end + 1;
+	}
+
+	/* copy the last chunk */
+	appendBinaryStringInfoNT(str, chunk_copy_start, strlen(chunk_copy_start));
+
+	appendStringInfoCharMacro(str, '\'');
+	str->data[str->len] = '\0';
+}
+
 /*
  * appendStringInfoChar
  *
diff --git a/src/include/lib/stringinfo.h b/src/include/lib/stringinfo.h
index e27942728e..4978ac9aa3 100644
--- a/src/include/lib/stringinfo.h
+++ b/src/include/lib/stringinfo.h
@@ -113,6 +113,13 @@ extern int	appendStringInfoVA(StringInfo str, const char *fmt, va_list args) pg_
  */
 extern void appendStringInfoString(StringInfo str, const char *s);
 
+/*
+ * appendStringInfoStringQuoted
+ * Append a null-terminated string to str, adding single quotes around
+ * and doubling all single quotes.
+ */
+extern void appendStringInfoStringQuoted(StringInfo str, const char *s);
+
 /*------------------------
  * appendStringInfoChar
  * Append a single byte to str.
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd9046619c..49a450b6d0 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -115,6 +115,7 @@ typedef struct ParamListInfoData
 	void	   *paramCompileArg;
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
+	char	   *logString;		/* string to log parameters */
 	int			numParams;		/* nominal/maximum # of Params represented */
 
 	/*
@@ -156,5 +157,9 @@ extern ParamListInfo copyParamList(ParamListInfo from);
 extern Size EstimateParamListSpace(ParamListInfo paramLI);
 extern void SerializeParamList(ParamListInfo paramLI, char **start_address);
 extern ParamListInfo RestoreParamList(char **start_address);
+extern void BuildParamLogString(ParamListInfo params, char **paramTextValues);
+extern void PutParamsInErrorContext(
+				ErrorContextCallback *new_error_context_entry,
+				ParamListInfo *params);
 
 #endif							/* PARAMS_H */
diff --git a/src/include/utils/elog.h b/src/include/utils/elog.h
index 9ab4b5470b..ecc78d2ae6 100644
--- a/src/include/utils/elog.h
+++ b/src/include/utils/elog.h
@@ -202,6 +202,7 @@ extern int	err_generic_string(int field, const char *str);
 extern int	geterrcode(void);
 extern int	geterrposition(void);
 extern int	getinternalerrposition(void);
+extern bool geterrshowstmt(void);
 
 
 /*----------
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 50098e63fe..41d5e1d14a 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
diff --git a/src/test/README b/src/test/README
index b5ccfc0cf6..22e624d8ba 100644
--- a/src/test/README
+++ b/src/test/README
@@ -12,8 +12,7 @@ authentication/
   Tests for authentication
 
 examples/
-  Demonstration programs for libpq that double as regression tests via
-  "make check"
+  Demonstration programs for libpq that double as regression tests
 
 isolation/
   Tests for concurrent behavior at the SQL level
diff --git a/src/test/examples/.gitignore b/src/test/examples/.gitignore
index 1957ec198f..007aaee590 100644
--- a/src/test/examples/.gitignore
+++ b/src/test/examples/.gitignore
@@ -2,5 +2,6 @@
 /testlibpq2
 /testlibpq3
 /testlibpq4
+/testlibpq5
 /testlo
 /testlo64
diff --git a/src/test/examples/Makefile b/src/test/examples/Makefile
index a67f456904..0407ca60bc 100644
--- a/src/test/examples/Makefile
+++ b/src/test/examples/Makefile
@@ -14,7 +14,7 @@ override CPPFLAGS := -I$(libpq_srcdir) $(CPPFLAGS)
 LDFLAGS_INTERNAL += $(libpq_pgport)
 
 
-PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlo testlo64
+PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlibpq5 testlo testlo64
 
 all: $(PROGS)
 
diff --git a/src/test/examples/testlibpq5.c b/src/test/examples/testlibpq5.c
new file mode 100644
index 0000000000..47a5e31335
--- /dev/null
+++ b/src/test/examples/testlibpq5.c
@@ -0,0 +1,193 @@
+/*
+ * src/test/examples/testlibpq5.c
+ *
+ * testlibpq5.c
+ *		Test logging of statement parameters in case of errors.
+ */
+
+#ifdef WIN32
+#include <windows.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/types.h>
+#include "libpq-fe.h"
+
+static void
+exit_nicely(PGconn *conn)
+{
+	PQfinish(conn);
+	exit(1);
+}
+
+int
+main(int argc, char **argv)
+{
+	const char *conninfo;
+	PGconn	   *conn;
+	PGresult   *res;
+	const char *paramValues[3];
+	int			paramLengths[3];
+	int			paramFormats[3];
+	uint32_t	binaryIntVal;
+
+	/*
+	 * If the user supplies a parameter on the command line, use it as the
+	 * conninfo string; otherwise default to setting dbname=postgres and using
+	 * environment variables or defaults for all other connection parameters.
+	 */
+	if (argc > 1)
+		conninfo = argv[1];
+	else
+		conninfo = "dbname = postgres";
+
+	/* Make a connection to the database */
+	conn = PQconnectdb(conninfo);
+
+	/* Check to see that the backend connection was successfully made */
+	if (PQstatus(conn) != CONNECTION_OK)
+	{
+		fprintf(stderr, "Connection to database failed: %s",
+				PQerrorMessage(conn));
+		exit_nicely(conn);
+	}
+
+	/* Set always-secure search path, so malicious users can't take control. */
+	res = PQexec(conn,
+				 "SELECT pg_catalog.set_config('search_path', '', false)");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/*
+	 * Transmit parameters in different forms and make a statement fail.  User
+	 * can then verify the server log.
+	 */
+	res = PQexec(conn, "SET log_parameters_on_error = on");
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/* emit error on parse stage */
+	paramValues[0] = (char *) "non-number -- parse";
+	paramLengths[0] = strlen(paramValues[2]) + 1;
+	paramFormats[0] = 0;		/* text */
+	res = PQexecParams(conn,
+					   "SELECT $1::int",
+					   1,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("text->int conversion error expected on parse stage, "
+		   "got an error message from server: %s\n",
+		   PQerrorMessage(conn));
+
+	/* emit error on bind stage */
+	paramValues[0] = (char *) "{malformed json -- bind :-{";
+	paramLengths[0] = strlen(paramValues[2]) + 1;
+	paramFormats[0] = 0;		/* text */
+	res = PQexecParams(conn,
+					   "SELECT (' ' || $1::text || ' ')::json",
+					   1,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Json parsing error expected on bind stage, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* divide by zero -- but server won't realize until execution; 0 params */
+	res = PQexecParams(conn,
+					   "SELECT 1 / (random() / 2)::int /*exec*/",
+					   0,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   NULL,
+					   NULL,
+					   NULL,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero on execution expected, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* divide by zero -- but server won't realize until execution; 3 params */
+	paramValues[0] = (char *) &binaryIntVal;
+	paramLengths[0] = sizeof(binaryIntVal);
+	paramFormats[0] = 1;		/* binary */
+	paramValues[1] = "2";
+	paramLengths[1] = strlen(paramValues[1]) + 1;
+	paramFormats[1] = 0;		/* text */
+	paramValues[2] = (char *) "everyone's little $$ in \"dollar\"";
+	paramLengths[2] = strlen(paramValues[2]) + 1;
+	paramFormats[2] = 0;		/* text */
+	res = PQexecParams(
+		conn,
+		"SELECT 1 / (random() / 2)::int + $1::int + $2::int, $3::text /*exec*/",
+		3,		/* # params */
+		NULL,	/* let the backend deduce param type */
+		paramValues,
+		paramLengths,
+		paramFormats,
+		1		/* ask for binary results */
+	);
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero on execution expected, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* close the connection to the database and cleanup */
+	PQfinish(conn);
+
+	return 0;
+}

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 4ec13f3311..b3a0d27861 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6597,6 +6597,29 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether bind parameters are logged when a statement is logged
+        as a result of <xref linkend="guc-log-min-error-statement"/>.
+        It adds some overhead, as postgres will compute and store textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged.
+        This setting has no effect on statements logged due to
+        <xref linkend="guc-log-min-duration-statement"/> or
+        <xref linkend="guc-log-statement"/> settings, as they are always logged
+        with parameters.
+        The default is <literal>off</literal>.
+        Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index cf4387e40f..7c1f86f5c5 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -15,12 +15,16 @@
 
 #include "postgres.h"
 
+#include "lib/stringinfo.h"
 #include "nodes/bitmapset.h"
 #include "nodes/params.h"
 #include "storage/shmem.h"
 #include "utils/datum.h"
+#include "utils/guc.h"
 #include "utils/lsyscache.h"
+#include "utils/memutils.h"
 
+static void LogParams(void *arg);
 
 /*
  * Allocate and initialize a new ParamListInfo structure.
@@ -44,6 +48,7 @@ makeParamList(int numParams)
 	retval->paramCompileArg = NULL;
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
+	retval->logString = NULL;
 	retval->numParams = numParams;
 
 	return retval;
@@ -58,6 +63,8 @@ makeParamList(int numParams)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * We also don't copy logString.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -221,6 +228,8 @@ SerializeParamList(ParamListInfo paramLI, char **start_address)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * We also don't copy logString.
  */
 ParamListInfo
 RestoreParamList(char **start_address)
@@ -251,3 +260,152 @@ RestoreParamList(char **start_address)
 
 	return paramLI;
 }
+
+/*
+ * BuildParamLogString - create a string to represent parameters list for
+ * logging and save it to params. If caller already knows textual
+ * representations for some or all parameters, it can pass an array of exactly
+ * params->numParams values as knownTextValues. It can contain NULLs for the
+ * individual values not known, or, if no text text values known at all the
+ * caller may pass NULL pointer.
+ */
+void
+BuildParamLogString(ParamListInfo params, char **knownTextValues)
+{
+	MemoryContext tmpCxt,
+				  oldCxt;
+	int logStringLen = 0;
+	StringInfoData logString;
+	char **textValues;
+
+	if (params->logString != NULL)
+		return;
+
+	Assert(params->paramFetch == NULL);
+
+	initStringInfo(&logString);
+
+	tmpCxt = AllocSetContextCreate(CurrentMemoryContext,
+								   "BuildParamLogString",
+								   ALLOCSET_DEFAULT_SIZES);
+	oldCxt = MemoryContextSwitchTo(tmpCxt);
+
+	textValues = (char **) palloc0(params->numParams * sizeof(char *));
+
+	/* calculate unknown text representations and pre-calculate byte lengths */
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData param = params->params[paramno];
+
+		/* reserve the space for the number of digits in paramno + 1 */
+		for (int d = paramno + 1; d > 0; d /= 10)
+			logStringLen++;
+
+		if (param.isnull)
+		{
+			logStringLen += 4; /* for "NULL" */
+		}
+		else
+		{
+			char *textValue,
+				 *s;
+
+			/* find out textValues[paramno] */
+			if (knownTextValues != NULL && knownTextValues[paramno] != NULL)
+			{
+				textValues[paramno] = knownTextValues[paramno];
+			}
+			else
+			{
+				Oid		typoutput;
+				bool	typisvarlena;
+				getTypeOutputInfo(param.ptype, &typoutput, &typisvarlena);
+				textValues[paramno] =
+								OidOutputFunctionCall(typoutput, param.value);
+			}
+
+			/* caluclate the space needed its printed length */
+			textValue = textValues[paramno];
+			for (s = textValue; *s != '\0'; s++)
+				if (*s == '\'')
+					logStringLen++; /* for quotes doubling */
+			/* string length + 2 for quotes */
+			logStringLen += s - textValue + 2;
+		}
+	}
+
+	/*
+	 * "$1 = something, " -- 6 bytes extra to the ordinal and the value;
+	 *  ^ ^^^         ^^
+	 * for the last one we don't need the comma and the space but need 0 byte
+	 */
+	logStringLen += params->numParams * 6 - 1;
+
+	MemoryContextSwitchTo(oldCxt);
+
+	/* enlarge at once to avoid multiple reallocations */
+	enlargeStringInfo(&logString, logStringLen);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		appendStringInfo(&logString,
+						 "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+		appendStringInfoStringQuoted(&logString, textValues[paramno]);
+	}
+
+	params->logString = logString.data;
+
+	MemoryContextDelete(tmpCxt);
+}
+
+/*
+ * PutParamsInErrorContext - if needed and possible,
+ * add an error context entry with bind parameters
+ *
+ * params is a pointer to ParamListInfo for the caller to be able to clear it
+ * if the actual ParamListInfo is gone
+ */
+void
+PutParamsInErrorContext(ErrorContextCallback *new_error_context_entry,
+						ParamListInfo *params)
+{
+	/*
+	 * Setting this anyway for the caller to be able to revert this operation
+	 * with `error_context_stack = new_error_context_entry->previous` regardless
+	 * whether we actually change the stack
+	 */
+	new_error_context_entry->previous = error_context_stack;
+
+	if (!log_parameters_on_error || *params == NULL
+								 || (*params)->logString == NULL)
+		return;
+
+	new_error_context_entry->callback = LogParams;
+	new_error_context_entry->arg = (void *)(params);
+	error_context_stack = new_error_context_entry;
+}
+
+/*
+ * LogParams - callback for printing parameters in error context
+ */
+static void
+LogParams(void *arg)
+{
+	ParamListInfo params = *((ParamListInfo *)(arg));
+
+	/*
+	 * XXX: errdetail_log copies the error message formatting, so we're
+	 * allocating a potentially large amounts of memory for the whole parameter
+	 * string again
+	 *
+	 * We can have NULL in params->logString if log_parameters_on_error was off
+	 * when we decided whether to call BuildParamLogString. In this rare case
+	 * we don't log the parameters: building the log string now wouldn't be safe
+	 * as we must't call user-defined I/O functions when in an aborted xact.
+	 */
+	if (params != NULL && params->logString != NULL
+							&& log_parameters_on_error && geterrshowstmt())
+		errdetail_log("parameters: %s", params->logString);
+}
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3b85e48333..9b562f7f01 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -177,7 +177,7 @@ static void forbidden_in_wal_sender(char firstchar);
 static List *pg_rewrite_query(Query *query);
 static bool check_log_statement(List *stmt_list);
 static int	errdetail_execute(List *raw_parsetree_list);
-static int	errdetail_params(ParamListInfo params);
+static int	errdetail_portal_params(Portal portal);
 static int	errdetail_abort(void);
 static int	errdetail_recovery_conflict(void);
 static void start_xact_command(void);
@@ -1596,23 +1596,24 @@ exec_parse_message(const char *query_string,	/* string to execute */
 static void
 exec_bind_message(StringInfo input_message)
 {
-	const char *portal_name;
-	const char *stmt_name;
-	int			numPFormats;
-	int16	   *pformats = NULL;
-	int			numParams;
-	int			numRFormats;
-	int16	   *rformats = NULL;
-	CachedPlanSource *psrc;
-	CachedPlan *cplan;
-	Portal		portal;
-	char	   *query_string;
-	char	   *saved_stmt_name;
-	ParamListInfo params;
-	MemoryContext oldContext;
-	bool		save_log_statement_stats = log_statement_stats;
-	bool		snapshot_set = false;
-	char		msec_str[32];
+	const char			*portal_name;
+	const char			*stmt_name;
+	int					 numPFormats;
+	int16				*pformats = NULL;
+	int					 numParams;
+	int					 numRFormats;
+	int16				*rformats = NULL;
+	CachedPlanSource	*psrc;
+	CachedPlan			*cplan;
+	Portal				 portal;
+	char				*query_string;
+	char				*saved_stmt_name;
+	ParamListInfo 		 params;
+	MemoryContext 		 oldContext;
+	bool				 save_log_statement_stats = log_statement_stats;
+	bool				 snapshot_set = false;
+	char				 msec_str[32];
+	ErrorContextCallback params_error_context;
 
 	/* Get the fixed part of the message */
 	portal_name = pq_getmsgstring(input_message);
@@ -1752,6 +1753,10 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		/* These are short-living, so we don't pollute the portal context */
+		char **knownTextValues = MemoryContextAllocZero(MessageContext,
+													numParams * sizeof(char *));
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1819,9 +1824,17 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				/*
+				 * If we need the parameter string, save it.
+				 * If not -- get rid of it.
+				 */
+				if (pstring)
+				{
+					if (log_parameters_on_error)
+						knownTextValues[paramno] = pstring;
+					else if (pstring != pbuf.data)
+						pfree(pstring);
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1871,6 +1884,9 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		if (log_parameters_on_error)
+			BuildParamLogString(params, knownTextValues);
 	}
 	else
 		params = NULL;
@@ -1878,6 +1894,9 @@ exec_bind_message(StringInfo input_message)
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
+	/* From now on, log parameters on error if enabled in GUC */
+	PutParamsInErrorContext(&params_error_context, &params);
+
 	/* Get the result format codes */
 	numRFormats = pq_getmsgint(input_message, 2);
 	if (numRFormats > 0)
@@ -1948,13 +1967,14 @@ exec_bind_message(StringInfo input_message)
 							*portal_name ? portal_name : "",
 							psrc->query_string),
 					 errhidestmt(true),
-					 errdetail_params(params)));
+					 errdetail_portal_params(portal)));
 			break;
 	}
 
 	if (save_log_statement_stats)
 		ShowUsage("BIND MESSAGE STATISTICS");
 
+	error_context_stack = params_error_context.previous;
 	debug_query_string = NULL;
 }
 
@@ -1966,19 +1986,20 @@ exec_bind_message(StringInfo input_message)
 static void
 exec_execute_message(const char *portal_name, long max_rows)
 {
-	CommandDest dest;
-	DestReceiver *receiver;
-	Portal		portal;
-	bool		completed;
-	char		completionTag[COMPLETION_TAG_BUFSIZE];
-	const char *sourceText;
-	const char *prepStmtName;
-	ParamListInfo portalParams;
-	bool		save_log_statement_stats = log_statement_stats;
-	bool		is_xact_command;
-	bool		execute_is_fetch;
-	bool		was_logged = false;
-	char		msec_str[32];
+	CommandDest			 dest;
+	DestReceiver		 *receiver;
+	Portal				 portal;
+	ParamListInfo		 params;
+	bool				 completed;
+	char				 completionTag[COMPLETION_TAG_BUFSIZE];
+	const char			*sourceText;
+	const char			*prepStmtName;
+	bool				 save_log_statement_stats = log_statement_stats;
+	bool				 is_xact_command;
+	bool				 execute_is_fetch;
+	bool				 was_logged = false;
+	char				 msec_str[32];
+	ErrorContextCallback params_error_context;
 
 	/* Adjust destination to tell printtup.c what to do */
 	dest = whereToSendOutput;
@@ -2002,6 +2023,10 @@ exec_execute_message(const char *portal_name, long max_rows)
 		return;
 	}
 
+	/* From now on, log parameters on error if enabled in GUC */
+	params = portal->portalParams;
+	PutParamsInErrorContext(&params_error_context, &params);
+
 	/* Does the portal contain a transaction command? */
 	is_xact_command = IsTransactionStmtList(portal->stmts);
 
@@ -2017,12 +2042,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 			prepStmtName = pstrdup(portal->prepStmtName);
 		else
 			prepStmtName = "<unnamed>";
-
-		/*
-		 * An xact command shouldn't have any parameters, which is a good
-		 * thing because they wouldn't be around after finish_xact_command.
-		 */
-		portalParams = NULL;
 	}
 	else
 	{
@@ -2031,7 +2050,6 @@ exec_execute_message(const char *portal_name, long max_rows)
 			prepStmtName = portal->prepStmtName;
 		else
 			prepStmtName = "<unnamed>";
-		portalParams = portal->portalParams;
 	}
 
 	/*
@@ -2083,7 +2101,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 						*portal_name ? portal_name : "",
 						sourceText),
 				 errhidestmt(true),
-				 errdetail_params(portalParams)));
+				 errdetail_portal_params(portal)));
 		was_logged = true;
 	}
 
@@ -2122,6 +2140,15 @@ exec_execute_message(const char *portal_name, long max_rows)
 	{
 		if (is_xact_command)
 		{
+			/*
+			 * The portal and its params may be destroyed during
+			 * finish_xact_command below. We only may need the portal for
+			 * parameters logging, but an xact command shouldn't have any
+			 * parameters.
+			 */
+			portal = NULL;
+			params = NULL;
+
 			/*
 			 * If this was a transaction control statement, commit it.  We
 			 * will start a new xact command for the next command (if any).
@@ -2175,13 +2202,14 @@ exec_execute_message(const char *portal_name, long max_rows)
 							*portal_name ? portal_name : "",
 							sourceText),
 					 errhidestmt(true),
-					 errdetail_params(portalParams)));
+					 errdetail_portal_params(portal)));
 			break;
 	}
 
 	if (save_log_statement_stats)
 		ShowUsage("EXECUTE MESSAGE STATISTICS");
 
+	error_context_stack = params_error_context.previous;
 	debug_query_string = NULL;
 }
 
@@ -2321,66 +2349,26 @@ errdetail_execute(List *raw_parsetree_list)
 }
 
 /*
- * errdetail_params
+ * errdetail_portal_params
  *
  * Add an errdetail() line showing bind-parameter data, if available.
  */
 static int
-errdetail_params(ParamListInfo params)
+errdetail_portal_params(Portal portal)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
+	if (portal != NULL &&
+		portal->portalParams &&
+		portal->portalParams->numParams > 0)
 	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
-
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-			char	   *p;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
-
-		pfree(param_str.data);
+		/*
+		 * We switch back to portal context for the params logString to be
+		 * generated there in order to reuse it in later invocations
+		 */
+		MemoryContext old_cxt = MemoryContextSwitchTo(portal->portalContext);
+		BuildParamLogString(portal->portalParams, NULL);
+		MemoryContextSwitchTo(old_cxt);
 
-		MemoryContextSwitchTo(oldcontext);
+		errdetail("parameters: %s", portal->portalParams->logString);
 	}
 
 	return 0;
diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index f46653632e..eb39c750f4 100644
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -1363,6 +1363,22 @@ getinternalerrposition(void)
 	return edata->internalpos;
 }
 
+/*
+ * geterrshowstmt --- return whether we are going to print the statement in the log
+ *
+ * This is only intended for use in error callback subroutines, since there
+ * is no other place outside elog.c where the concept is meaningful.
+ */
+bool
+geterrshowstmt(void)
+{
+	ErrorData  *edata = &errordata[errordata_stack_depth];
+
+	return is_log_level_output(edata->elevel, log_min_error_statement) &&
+		debug_query_string != NULL &&
+		!edata->hide_stmt;
+}
+
 
 /*
  * elog_start --- startup for old-style API
@@ -2742,7 +2758,7 @@ static void
 write_csvlog(ErrorData *edata)
 {
 	StringInfoData buf;
-	bool		print_stmt = false;
+	bool print_stmt = geterrshowstmt();
 
 	/* static counter for line numbers */
 	static long log_line_number = 0;
@@ -2886,10 +2902,6 @@ write_csvlog(ErrorData *edata)
 	appendStringInfoChar(&buf, ',');
 
 	/* user query --- only reported if not disabled by the caller */
-	if (is_log_level_output(edata->elevel, log_min_error_statement) &&
-		debug_query_string != NULL &&
-		!edata->hide_stmt)
-		print_stmt = true;
 	if (print_stmt)
 		appendCSVLiteral(&buf, debug_query_string);
 	appendStringInfoChar(&buf, ',');
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 5fccc9683e..1be1f1fb29 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -486,6 +486,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1300,6 +1301,15 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
+	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
 	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 46a06ffacd..91cdc06fc4 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -544,6 +544,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
index a50e587da9..300fa4527b 100644
--- a/src/common/stringinfo.c
+++ b/src/common/stringinfo.c
@@ -178,6 +178,42 @@ appendStringInfoString(StringInfo str, const char *s)
 	appendBinaryStringInfo(str, s, strlen(s));
 }
 
+/*
+ * appendStringInfoStringQuoted
+ *
+ * Append a null-terminated string to str, adding single quotes around
+ * and doubling all single quotes.
+ */
+void
+appendStringInfoStringQuoted(StringInfo str, const char *s)
+{
+	const char *chunk_search_start = s,
+			   *chunk_copy_start = s,
+			   *chunk_end;
+
+	Assert(str != NULL);
+
+	appendStringInfoCharMacro(str, '\'');
+
+	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
+	{
+		/* copy including the found delimiting ' */
+		appendBinaryStringInfoNT(str,
+								 chunk_copy_start,
+								 chunk_end - chunk_copy_start + 1);
+
+		/* in order to double it, include this ' into the next chunk as well*/
+		chunk_copy_start = chunk_end;
+		chunk_search_start = chunk_end + 1;
+	}
+
+	/* copy the last chunk */
+	appendBinaryStringInfoNT(str, chunk_copy_start, strlen(chunk_copy_start));
+
+	appendStringInfoCharMacro(str, '\'');
+	str->data[str->len] = '\0';
+}
+
 /*
  * appendStringInfoChar
  *
diff --git a/src/include/lib/stringinfo.h b/src/include/lib/stringinfo.h
index e27942728e..4978ac9aa3 100644
--- a/src/include/lib/stringinfo.h
+++ b/src/include/lib/stringinfo.h
@@ -113,6 +113,13 @@ extern int	appendStringInfoVA(StringInfo str, const char *fmt, va_list args) pg_
  */
 extern void appendStringInfoString(StringInfo str, const char *s);
 
+/*
+ * appendStringInfoStringQuoted
+ * Append a null-terminated string to str, adding single quotes around
+ * and doubling all single quotes.
+ */
+extern void appendStringInfoStringQuoted(StringInfo str, const char *s);
+
 /*------------------------
  * appendStringInfoChar
  * Append a single byte to str.
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd9046619c..49a450b6d0 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -115,6 +115,7 @@ typedef struct ParamListInfoData
 	void	   *paramCompileArg;
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
+	char	   *logString;		/* string to log parameters */
 	int			numParams;		/* nominal/maximum # of Params represented */
 
 	/*
@@ -156,5 +157,9 @@ extern ParamListInfo copyParamList(ParamListInfo from);
 extern Size EstimateParamListSpace(ParamListInfo paramLI);
 extern void SerializeParamList(ParamListInfo paramLI, char **start_address);
 extern ParamListInfo RestoreParamList(char **start_address);
+extern void BuildParamLogString(ParamListInfo params, char **paramTextValues);
+extern void PutParamsInErrorContext(
+				ErrorContextCallback *new_error_context_entry,
+				ParamListInfo *params);
 
 #endif							/* PARAMS_H */
diff --git a/src/include/utils/elog.h b/src/include/utils/elog.h
index 9ab4b5470b..ecc78d2ae6 100644
--- a/src/include/utils/elog.h
+++ b/src/include/utils/elog.h
@@ -202,6 +202,7 @@ extern int	err_generic_string(int field, const char *str);
 extern int	geterrcode(void);
 extern int	geterrposition(void);
 extern int	getinternalerrposition(void);
+extern bool geterrshowstmt(void);
 
 
 /*----------
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 50098e63fe..41d5e1d14a 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
diff --git a/src/test/README b/src/test/README
index b5ccfc0cf6..22e624d8ba 100644
--- a/src/test/README
+++ b/src/test/README
@@ -12,8 +12,7 @@ authentication/
   Tests for authentication
 
 examples/
-  Demonstration programs for libpq that double as regression tests via
-  "make check"
+  Demonstration programs for libpq that double as regression tests
 
 isolation/
   Tests for concurrent behavior at the SQL level
diff --git a/src/test/examples/.gitignore b/src/test/examples/.gitignore
index 1957ec198f..007aaee590 100644
--- a/src/test/examples/.gitignore
+++ b/src/test/examples/.gitignore
@@ -2,5 +2,6 @@
 /testlibpq2
 /testlibpq3
 /testlibpq4
+/testlibpq5
 /testlo
 /testlo64
diff --git a/src/test/examples/Makefile b/src/test/examples/Makefile
index a67f456904..0407ca60bc 100644
--- a/src/test/examples/Makefile
+++ b/src/test/examples/Makefile
@@ -14,7 +14,7 @@ override CPPFLAGS := -I$(libpq_srcdir) $(CPPFLAGS)
 LDFLAGS_INTERNAL += $(libpq_pgport)
 
 
-PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlo testlo64
+PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlibpq5 testlo testlo64
 
 all: $(PROGS)
 
diff --git a/src/test/examples/testlibpq5.c b/src/test/examples/testlibpq5.c
new file mode 100644
index 0000000000..47a5e31335
--- /dev/null
+++ b/src/test/examples/testlibpq5.c
@@ -0,0 +1,193 @@
+/*
+ * src/test/examples/testlibpq5.c
+ *
+ * testlibpq5.c
+ *		Test logging of statement parameters in case of errors.
+ */
+
+#ifdef WIN32
+#include <windows.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/types.h>
+#include "libpq-fe.h"
+
+static void
+exit_nicely(PGconn *conn)
+{
+	PQfinish(conn);
+	exit(1);
+}
+
+int
+main(int argc, char **argv)
+{
+	const char *conninfo;
+	PGconn	   *conn;
+	PGresult   *res;
+	const char *paramValues[3];
+	int			paramLengths[3];
+	int			paramFormats[3];
+	uint32_t	binaryIntVal;
+
+	/*
+	 * If the user supplies a parameter on the command line, use it as the
+	 * conninfo string; otherwise default to setting dbname=postgres and using
+	 * environment variables or defaults for all other connection parameters.
+	 */
+	if (argc > 1)
+		conninfo = argv[1];
+	else
+		conninfo = "dbname = postgres";
+
+	/* Make a connection to the database */
+	conn = PQconnectdb(conninfo);
+
+	/* Check to see that the backend connection was successfully made */
+	if (PQstatus(conn) != CONNECTION_OK)
+	{
+		fprintf(stderr, "Connection to database failed: %s",
+				PQerrorMessage(conn));
+		exit_nicely(conn);
+	}
+
+	/* Set always-secure search path, so malicious users can't take control. */
+	res = PQexec(conn,
+				 "SELECT pg_catalog.set_config('search_path', '', false)");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/*
+	 * Transmit parameters in different forms and make a statement fail.  User
+	 * can then verify the server log.
+	 */
+	res = PQexec(conn, "SET log_parameters_on_error = on");
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/* emit error on parse stage */
+	paramValues[0] = (char *) "non-number -- parse";
+	paramLengths[0] = strlen(paramValues[2]) + 1;
+	paramFormats[0] = 0;		/* text */
+	res = PQexecParams(conn,
+					   "SELECT $1::int",
+					   1,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("text->int conversion error expected on parse stage, "
+		   "got an error message from server: %s\n",
+		   PQerrorMessage(conn));
+
+	/* emit error on bind stage */
+	paramValues[0] = (char *) "{malformed json -- bind :-{";
+	paramLengths[0] = strlen(paramValues[2]) + 1;
+	paramFormats[0] = 0;		/* text */
+	res = PQexecParams(conn,
+					   "SELECT (' ' || $1::text || ' ')::json",
+					   1,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Json parsing error expected on bind stage, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* divide by zero -- but server won't realize until execution; 0 params */
+	res = PQexecParams(conn,
+					   "SELECT 1 / (random() / 2)::int /*exec*/",
+					   0,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   NULL,
+					   NULL,
+					   NULL,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero on execution expected, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* divide by zero -- but server won't realize until execution; 3 params */
+	paramValues[0] = (char *) &binaryIntVal;
+	paramLengths[0] = sizeof(binaryIntVal);
+	paramFormats[0] = 1;		/* binary */
+	paramValues[1] = "2";
+	paramLengths[1] = strlen(paramValues[1]) + 1;
+	paramFormats[1] = 0;		/* text */
+	paramValues[2] = (char *) "everyone's little $$ in \"dollar\"";
+	paramLengths[2] = strlen(paramValues[2]) + 1;
+	paramFormats[2] = 0;		/* text */
+	res = PQexecParams(
+		conn,
+		"SELECT 1 / (random() / 2)::int + $1::int + $2::int, $3::text /*exec*/",
+		3,		/* # params */
+		NULL,	/* let the backend deduce param type */
+		paramValues,
+		paramLengths,
+		paramFormats,
+		1		/* ask for binary results */
+	);
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero on execution expected, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* close the connection to the database and cleanup */
+	PQfinish(conn);
+
+	return 0;
+}

From 99cf1d122bc935a4060c6b359fb2c262035039df Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Tue, 3 Dec 2019 10:08:35 -0300
Subject: [PATCH] Add appendStringInfoStringQuoted
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Simplifies some coding that prints parameters, as well as optimize to do
it per non-quote chunks instead of per byte.

Author: Alexey Bashtanov and Álvaro Herrera, after a suggestion from Andres Freund
Discussion: https://postgr.es/m/20190920203905.xkv5udsd5dxfs6tr@alap3.anarazel.de
---
 src/backend/tcop/postgres.c  | 10 +--------
 src/common/stringinfo.c      | 40 ++++++++++++++++++++++++++++++++++++
 src/include/lib/stringinfo.h |  7 +++++++
 src/pl/plpgsql/src/pl_exec.c | 34 ++++++++----------------------
 4 files changed, 56 insertions(+), 35 deletions(-)

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3b85e48333..0bff20ad67 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -2348,7 +2348,6 @@ errdetail_params(ParamListInfo params)
 			Oid			typoutput;
 			bool		typisvarlena;
 			char	   *pstring;
-			char	   *p;
 
 			appendStringInfo(&param_str, "%s$%d = ",
 							 paramno > 0 ? ", " : "",
@@ -2364,14 +2363,7 @@ errdetail_params(ParamListInfo params)
 
 			pstring = OidOutputFunctionCall(typoutput, prm->value);
 
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
+			appendStringInfoStringQuoted(&param_str, pstring);
 
 			pfree(pstring);
 		}
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
index a50e587da9..f4dddf8223 100644
--- a/src/common/stringinfo.c
+++ b/src/common/stringinfo.c
@@ -178,6 +178,46 @@ appendStringInfoString(StringInfo str, const char *s)
 	appendBinaryStringInfo(str, s, strlen(s));
 }
 
+/*
+ * appendStringInfoStringQuoted
+ *
+ * Append a null-terminated string to str, adding single quotes around it
+ * and doubling all single quotes.
+ */
+void
+appendStringInfoStringQuoted(StringInfo str, const char *s)
+{
+	const char *chunk_search_start = s,
+			   *chunk_copy_start = s,
+			   *chunk_end;
+	int			len;
+
+	Assert(str != NULL);
+
+	appendStringInfoCharMacro(str, '\'');
+
+	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
+	{
+		/* copy including the found delimiting ' */
+		appendBinaryStringInfoNT(str,
+								 chunk_copy_start,
+								 chunk_end - chunk_copy_start + 1);
+
+		/* in order to double it, include this ' into the next chunk as well */
+		chunk_copy_start = chunk_end;
+		chunk_search_start = chunk_end + 1;
+	}
+
+	/* copy the last chunk, ensuring sufficient space for final bytes */
+	len = strlen(chunk_copy_start);
+	enlargeStringInfo(str, len + 2);
+	appendBinaryStringInfoNT(str, chunk_copy_start, len);
+
+	/* add terminators */
+	appendStringInfoCharMacro(str, '\'');
+	str->data[str->len] = '\0';
+}
+
 /*
  * appendStringInfoChar
  *
diff --git a/src/include/lib/stringinfo.h b/src/include/lib/stringinfo.h
index e27942728e..7de2773e1f 100644
--- a/src/include/lib/stringinfo.h
+++ b/src/include/lib/stringinfo.h
@@ -113,6 +113,13 @@ extern int	appendStringInfoVA(StringInfo str, const char *fmt, va_list args) pg_
  */
 extern void appendStringInfoString(StringInfo str, const char *s);
 
+/*------------------------
+ * appendStringInfoStringQuoted
+ * Append a null-terminated string to str, adding single quotes around it
+ * and doubling all single quotes.
+ */
+extern void appendStringInfoStringQuoted(StringInfo str, const char *s);
+
 /*------------------------
  * appendStringInfoChar
  * Append a single byte to str.
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 4f0de7a811..23553a6948 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -8611,19 +8611,10 @@ format_expr_params(PLpgSQL_execstate *estate,
 		if (paramisnull)
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, paramdatum, paramtypeid);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 paramdatum,
+																 paramtypeid));
 
 		paramno++;
 	}
@@ -8661,19 +8652,10 @@ format_preparedparamsdata(PLpgSQL_execstate *estate,
 		if (ppd->nulls[paramno] == 'n')
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, ppd->values[paramno], ppd->types[paramno]);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 ppd->values[paramno],
+																 ppd->types[paramno]));
 	}
 
 	MemoryContextSwitchTo(oldcontext);
-- 
2.20.1

From 9a92076e53a6664ec61c5f475310c5d6edb91d90 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Wed, 4 Dec 2019 11:02:34 -0300
Subject: [PATCH v3 1/3] Add strndup / pg_strndup

The former is now a POSIX function.  We already had pnstrdup, but it was
not offered to frontend code.
---
 configure                        | 23 +++++++++++++++++++++++
 configure.in                     |  3 ++-
 src/common/fe_memutils.c         | 26 ++++++++++++++++++++++++++
 src/include/common/fe_memutils.h |  2 ++
 src/include/pg_config.h.in       |  7 +++++++
 src/include/pg_config.h.win32    |  7 +++++++
 src/include/port.h               |  4 ++++
 src/port/strndup.c               | 32 ++++++++++++++++++++++++++++++++
 8 files changed, 103 insertions(+), 1 deletion(-)
 create mode 100644 src/port/strndup.c

diff --git a/configure b/configure
index 1d88983b34..fd8c759473 100755
--- a/configure
+++ b/configure
@@ -15482,6 +15482,16 @@ fi
 cat >>confdefs.h <<_ACEOF
 #define HAVE_DECL_STRLCPY $ac_have_decl
 _ACEOF
+ac_fn_c_check_decl "$LINENO" "strndup" "ac_cv_have_decl_strndup" "$ac_includes_default"
+if test "x$ac_cv_have_decl_strndup" = xyes; then :
+  ac_have_decl=1
+else
+  ac_have_decl=0
+fi
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_DECL_STRNDUP $ac_have_decl
+_ACEOF
 ac_fn_c_check_decl "$LINENO" "strnlen" "ac_cv_have_decl_strnlen" "$ac_includes_default"
 if test "x$ac_cv_have_decl_strnlen" = xyes; then :
   ac_have_decl=1
@@ -15815,6 +15825,19 @@ esac
 
 fi
 
+ac_fn_c_check_func "$LINENO" "strndup" "ac_cv_func_strndup"
+if test "x$ac_cv_func_strndup" = xyes; then :
+  $as_echo "#define HAVE_STRNDUP 1" >>confdefs.h
+
+else
+  case " $LIBOBJS " in
+  *" strndup.$ac_objext "* ) ;;
+  *) LIBOBJS="$LIBOBJS strndup.$ac_objext"
+ ;;
+esac
+
+fi
+
 ac_fn_c_check_func "$LINENO" "strnlen" "ac_cv_func_strnlen"
 if test "x$ac_cv_func_strnlen" = xyes; then :
   $as_echo "#define HAVE_STRNLEN 1" >>confdefs.h
diff --git a/configure.in b/configure.in
index a2cb20b5e3..11f66d19c3 100644
--- a/configure.in
+++ b/configure.in
@@ -1679,7 +1679,7 @@ AC_CHECK_DECLS(posix_fadvise, [], [], [#include <fcntl.h>])
 ]) # fi
 
 AC_CHECK_DECLS(fdatasync, [], [], [#include <unistd.h>])
-AC_CHECK_DECLS([strlcat, strlcpy, strnlen])
+AC_CHECK_DECLS([strlcat, strlcpy, strndup, strnlen])
 # This is probably only present on macOS, but may as well check always
 AC_CHECK_DECLS(F_FULLFSYNC, [], [], [#include <fcntl.h>])
 
@@ -1738,6 +1738,7 @@ AC_REPLACE_FUNCS(m4_normalize([
 	srandom
 	strlcat
 	strlcpy
+	strndup
 	strnlen
 	strtof
 ]))
diff --git a/src/common/fe_memutils.c b/src/common/fe_memutils.c
index ce99b4f4da..896e5d46ca 100644
--- a/src/common/fe_memutils.c
+++ b/src/common/fe_memutils.c
@@ -101,6 +101,26 @@ pg_strdup(const char *in)
 	return tmp;
 }
 
+char *
+pg_strndup(const char *in, size_t size)
+{
+	char	   *tmp;
+
+	if (!in)
+	{
+		fprintf(stderr,
+				_("cannot duplicate null pointer (internal error)\n"));
+		exit(EXIT_FAILURE);
+	}
+	tmp = strndup(in, size);
+	if (!tmp)
+	{
+		fprintf(stderr, _("out of memory\n"));
+		exit(EXIT_FAILURE);
+	}
+	return tmp;
+}
+
 void
 pg_free(void *ptr)
 {
@@ -142,6 +162,12 @@ pstrdup(const char *in)
 	return pg_strdup(in);
 }
 
+char *
+pnstrdup(const char *in, Size size)
+{
+	return pg_strndup(in, size);
+}
+
 void *
 repalloc(void *pointer, Size size)
 {
diff --git a/src/include/common/fe_memutils.h b/src/include/common/fe_memutils.h
index a1e5940d31..c8797ffe38 100644
--- a/src/include/common/fe_memutils.h
+++ b/src/include/common/fe_memutils.h
@@ -23,6 +23,7 @@
  * (except pg_malloc_extended with MCXT_ALLOC_NO_OOM)
  */
 extern char *pg_strdup(const char *in);
+extern char *pg_strndup(const char *in, size_t size);
 extern void *pg_malloc(size_t size);
 extern void *pg_malloc0(size_t size);
 extern void *pg_malloc_extended(size_t size, int flags);
@@ -31,6 +32,7 @@ extern void pg_free(void *pointer);
 
 /* Equivalent functions, deliberately named the same as backend functions */
 extern char *pstrdup(const char *in);
+extern char *pnstrdup(const char *in, Size size);
 extern void *palloc(Size size);
 extern void *palloc0(Size size);
 extern void *palloc_extended(Size size, int flags);
diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in
index c208dcdfc7..1db3f1b1e8 100644
--- a/src/include/pg_config.h.in
+++ b/src/include/pg_config.h.in
@@ -170,6 +170,10 @@
    don't. */
 #undef HAVE_DECL_STRLCPY
 
+/* Define to 1 if you have the declaration of `strndup', and to 0 if you
+   don't. */
+#undef HAVE_DECL_STRNDUP
+
 /* Define to 1 if you have the declaration of `strnlen', and to 0 if you
    don't. */
 #undef HAVE_DECL_STRNLEN
@@ -545,6 +549,9 @@
 /* Define to 1 if you have the `strlcpy' function. */
 #undef HAVE_STRLCPY
 
+/* Define to 1 if you have the `strndup' function. */
+#undef HAVE_STRNDUP
+
 /* Define to 1 if you have the `strnlen' function. */
 #undef HAVE_STRNLEN
 
diff --git a/src/include/pg_config.h.win32 b/src/include/pg_config.h.win32
index 6c98ef4916..2ff2c3d4a8 100644
--- a/src/include/pg_config.h.win32
+++ b/src/include/pg_config.h.win32
@@ -129,6 +129,10 @@
    don't. */
 #define HAVE_DECL_RTLD_NOW 0
 
+/* Define to 1 if you have the declaration of `strndup', and to 0 if you
+   don't. */
+#undef HAVE_DECL_STRNDUP
+
 /* Define to 1 if you have the declaration of `strnlen', and to 0 if you
    don't. */
 #define HAVE_DECL_STRNLEN 1
@@ -297,6 +301,9 @@
 /* Define to 1 if you have the <pam/pam_appl.h> header file. */
 /* #undef HAVE_PAM_PAM_APPL_H */
 
+/* Define to 1 if you have the `strndup' function. */
+#undef HAVE_STRNDUP
+
 /* Define to 1 if you have the `strnlen' function. */
 #define HAVE_STRNLEN 1
 
diff --git a/src/include/port.h b/src/include/port.h
index 10dcb5f0a6..e5d4486eb2 100644
--- a/src/include/port.h
+++ b/src/include/port.h
@@ -430,6 +430,10 @@ extern size_t strlcat(char *dst, const char *src, size_t siz);
 extern size_t strlcpy(char *dst, const char *src, size_t siz);
 #endif
 
+#if !HAVE_DECL_STRNDUP
+extern char *strndup(char *src, size_t siz);
+#endif
+
 #if !HAVE_DECL_STRNLEN
 extern size_t strnlen(const char *str, size_t maxlen);
 #endif
diff --git a/src/port/strndup.c b/src/port/strndup.c
new file mode 100644
index 0000000000..eba41a0498
--- /dev/null
+++ b/src/port/strndup.c
@@ -0,0 +1,32 @@
+/*
+ * strndup.c
+ *      Fallback implementation of strndup().
+ *
+ * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ *    src/port/strndup.c
+ */
+
+#include "c.h"
+
+/*
+ * Implementation of posix' strndup for systems where it's not available.
+ */
+char *
+strndup(const char *str, size_t siz)
+{
+	char   *dst;
+	int		len;
+
+	len = strnlen(str, siz);
+	dst = malloc(len + 1);
+	if (dst == NULL)
+		return NULL;
+
+	memcpy(dst, str, len);
+	dst[len + 1] = '\0';
+
+	return dst;
+}
-- 
2.20.1

From c8eea42dcd441fdf0c7ded15538bd113dfbf0ff7 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Tue, 3 Dec 2019 10:08:35 -0300
Subject: [PATCH v3 2/3] Add appendStringInfoStringQuoted
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Simplifies some coding that prints parameters, as well as optimize to do
it per non-quote chunks instead of per byte.

Author: Alexey Bashtanov and Álvaro Herrera, after a suggestion from Andres Freund
Discussion: https://postgr.es/m/20190920203905.xkv5udsd5dxfs6tr@alap3.anarazel.de
---
 src/backend/tcop/postgres.c  | 10 +--------
 src/common/stringinfo.c      | 40 ++++++++++++++++++++++++++++++++++++
 src/include/lib/stringinfo.h |  7 +++++++
 src/pl/plpgsql/src/pl_exec.c | 34 ++++++++----------------------
 4 files changed, 56 insertions(+), 35 deletions(-)

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3b85e48333..0bff20ad67 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -2348,7 +2348,6 @@ errdetail_params(ParamListInfo params)
 			Oid			typoutput;
 			bool		typisvarlena;
 			char	   *pstring;
-			char	   *p;
 
 			appendStringInfo(&param_str, "%s$%d = ",
 							 paramno > 0 ? ", " : "",
@@ -2364,14 +2363,7 @@ errdetail_params(ParamListInfo params)
 
 			pstring = OidOutputFunctionCall(typoutput, prm->value);
 
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
+			appendStringInfoStringQuoted(&param_str, pstring);
 
 			pfree(pstring);
 		}
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
index a50e587da9..f4dddf8223 100644
--- a/src/common/stringinfo.c
+++ b/src/common/stringinfo.c
@@ -178,6 +178,46 @@ appendStringInfoString(StringInfo str, const char *s)
 	appendBinaryStringInfo(str, s, strlen(s));
 }
 
+/*
+ * appendStringInfoStringQuoted
+ *
+ * Append a null-terminated string to str, adding single quotes around it
+ * and doubling all single quotes.
+ */
+void
+appendStringInfoStringQuoted(StringInfo str, const char *s)
+{
+	const char *chunk_search_start = s,
+			   *chunk_copy_start = s,
+			   *chunk_end;
+	int			len;
+
+	Assert(str != NULL);
+
+	appendStringInfoCharMacro(str, '\'');
+
+	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
+	{
+		/* copy including the found delimiting ' */
+		appendBinaryStringInfoNT(str,
+								 chunk_copy_start,
+								 chunk_end - chunk_copy_start + 1);
+
+		/* in order to double it, include this ' into the next chunk as well */
+		chunk_copy_start = chunk_end;
+		chunk_search_start = chunk_end + 1;
+	}
+
+	/* copy the last chunk, ensuring sufficient space for final bytes */
+	len = strlen(chunk_copy_start);
+	enlargeStringInfo(str, len + 2);
+	appendBinaryStringInfoNT(str, chunk_copy_start, len);
+
+	/* add terminators */
+	appendStringInfoCharMacro(str, '\'');
+	str->data[str->len] = '\0';
+}
+
 /*
  * appendStringInfoChar
  *
diff --git a/src/include/lib/stringinfo.h b/src/include/lib/stringinfo.h
index e27942728e..7de2773e1f 100644
--- a/src/include/lib/stringinfo.h
+++ b/src/include/lib/stringinfo.h
@@ -113,6 +113,13 @@ extern int	appendStringInfoVA(StringInfo str, const char *fmt, va_list args) pg_
  */
 extern void appendStringInfoString(StringInfo str, const char *s);
 
+/*------------------------
+ * appendStringInfoStringQuoted
+ * Append a null-terminated string to str, adding single quotes around it
+ * and doubling all single quotes.
+ */
+extern void appendStringInfoStringQuoted(StringInfo str, const char *s);
+
 /*------------------------
  * appendStringInfoChar
  * Append a single byte to str.
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 4f0de7a811..23553a6948 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -8611,19 +8611,10 @@ format_expr_params(PLpgSQL_execstate *estate,
 		if (paramisnull)
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, paramdatum, paramtypeid);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 paramdatum,
+																 paramtypeid));
 
 		paramno++;
 	}
@@ -8661,19 +8652,10 @@ format_preparedparamsdata(PLpgSQL_execstate *estate,
 		if (ppd->nulls[paramno] == 'n')
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, ppd->values[paramno], ppd->types[paramno]);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 ppd->values[paramno],
+																 ppd->types[paramno]));
 	}
 
 	MemoryContextSwitchTo(oldcontext);
-- 
2.20.1

From a34b4728658891cb7d37433877efd0b706331dd3 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Tue, 3 Dec 2019 18:12:25 -0300
Subject: [PATCH v3 3/3] Restrict length printed by
 appendStringInfoStringQuoted

---
 src/backend/tcop/postgres.c           |  2 +-
 src/common/stringinfo.c               | 49 +++++++++++++++++++++------
 src/include/lib/stringinfo.h          |  3 +-
 src/pl/plpgsql/src/pl_exec.c          |  6 ++--
 src/test/regress/expected/plpgsql.out | 14 ++++++++
 src/test/regress/sql/plpgsql.sql      | 13 +++++++
 6 files changed, 72 insertions(+), 15 deletions(-)

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 0bff20ad67..c38ea2c743 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -2363,7 +2363,7 @@ errdetail_params(ParamListInfo params)
 
 			pstring = OidOutputFunctionCall(typoutput, prm->value);
 
-			appendStringInfoStringQuoted(&param_str, pstring);
+			appendStringInfoStringQuoted(&param_str, pstring, 64);
 
 			pfree(pstring);
 		}
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
index f4dddf8223..6f7555ef96 100644
--- a/src/common/stringinfo.c
+++ b/src/common/stringinfo.c
@@ -185,15 +185,34 @@ appendStringInfoString(StringInfo str, const char *s)
  * and doubling all single quotes.
  */
 void
-appendStringInfoStringQuoted(StringInfo str, const char *s)
+appendStringInfoStringQuoted(StringInfo str, const char *s, int maxlen)
 {
-	const char *chunk_search_start = s,
-			   *chunk_copy_start = s,
+	char	   *copy = NULL;
+	const char *chunk_search_start,
+			   *chunk_copy_start,
 			   *chunk_end;
-	int			len;
+	bool		ellipsis;
 
 	Assert(str != NULL);
 
+	if (maxlen > 0)
+	{
+		copy = pnstrdup(s, maxlen);
+		chunk_search_start = copy;
+		chunk_copy_start = copy;
+
+		ellipsis = strnlen(s, maxlen + 1) > maxlen;
+		/* enlarge while we can do so cheaply */
+		enlargeStringInfo(str, maxlen);
+	}
+	else
+	{
+		chunk_search_start = s;
+		chunk_copy_start = s;
+
+		ellipsis = false;
+	}
+
 	appendStringInfoCharMacro(str, '\'');
 
 	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
@@ -208,14 +227,22 @@ appendStringInfoStringQuoted(StringInfo str, const char *s)
 		chunk_search_start = chunk_end + 1;
 	}
 
-	/* copy the last chunk, ensuring sufficient space for final bytes */
-	len = strlen(chunk_copy_start);
-	enlargeStringInfo(str, len + 2);
-	appendBinaryStringInfoNT(str, chunk_copy_start, len);
+	/* copy the last chunk and terminate */
+	if (ellipsis)
+		appendStringInfo(str, "%s...'", chunk_copy_start);
+	else
+	{
+		int		len = strlen(chunk_copy_start);
 
-	/* add terminators */
-	appendStringInfoCharMacro(str, '\'');
-	str->data[str->len] = '\0';
+		/* ensure sufficient space for terminators */
+		enlargeStringInfo(str, len + 2);
+		appendBinaryStringInfoNT(str, chunk_copy_start, len);
+		appendStringInfoCharMacro(str, '\'');
+		str->data[str->len] = '\0';
+	}
+
+	if (copy)
+		pfree(copy);
 }
 
 /*
diff --git a/src/include/lib/stringinfo.h b/src/include/lib/stringinfo.h
index 7de2773e1f..956ccbba45 100644
--- a/src/include/lib/stringinfo.h
+++ b/src/include/lib/stringinfo.h
@@ -118,7 +118,8 @@ extern void appendStringInfoString(StringInfo str, const char *s);
  * Append a null-terminated string to str, adding single quotes around it
  * and doubling all single quotes.
  */
-extern void appendStringInfoStringQuoted(StringInfo str, const char *s);
+extern void appendStringInfoStringQuoted(StringInfo str, const char *s,
+										 int maxlen);
 
 /*------------------------
  * appendStringInfoChar
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 23553a6948..752a66f379 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -8614,7 +8614,8 @@ format_expr_params(PLpgSQL_execstate *estate,
 			appendStringInfoStringQuoted(&paramstr,
 										 convert_value_to_string(estate,
 																 paramdatum,
-																 paramtypeid));
+																 paramtypeid),
+										 64);
 
 		paramno++;
 	}
@@ -8655,7 +8656,8 @@ format_preparedparamsdata(PLpgSQL_execstate *estate,
 			appendStringInfoStringQuoted(&paramstr,
 										 convert_value_to_string(estate,
 																 ppd->values[paramno],
-																 ppd->types[paramno]));
+																 ppd->types[paramno]),
+										 64);
 	}
 
 	MemoryContextSwitchTo(oldcontext);
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index e85b29455e..a53ae28548 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -2656,6 +2656,20 @@ create or replace function stricttest() returns void as $$
 declare
 x record;
 p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+select stricttest();
+ERROR:  query returned no rows
+DETAIL:  parameters: p1 = '2', p3 = '''Valame Dios!'' dijo Sancho; ''no le dije yo a vuestra merced que ...'
+CONTEXT:  PL/pgSQL function stricttest() line 8 at SQL statement
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
 p3 text := 'foo';
 begin
   -- too many rows
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index 70deadfbea..d841d8c0f9 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2280,6 +2280,19 @@ end$$ language plpgsql;
 
 select stricttest();
 
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+
+select stricttest();
+
 create or replace function stricttest() returns void as $$
 declare
 x record;
-- 
2.20.1

From 1c5ffb2fb828a3589564d2f8af828e1be0549956 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Tue, 3 Dec 2019 10:08:35 -0300
Subject: [PATCH v15 1/2] Add appendStringInfoStringQuoted
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Simplifies some coding that prints parameters, as well as optimize to do
it per non-quote chunks instead of per byte.

Author: Alexey Bashtanov and Álvaro Herrera, after a suggestion from Andres Freund
Discussion: https://postgr.es/m/20190920203905.xkv5udsd5dxfs6tr@alap3.anarazel.de
---
 src/backend/tcop/postgres.c  | 10 +--------
 src/common/stringinfo.c      | 40 ++++++++++++++++++++++++++++++++++++
 src/include/lib/stringinfo.h |  7 +++++++
 src/pl/plpgsql/src/pl_exec.c | 34 ++++++++----------------------
 4 files changed, 56 insertions(+), 35 deletions(-)

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3b85e48333..0bff20ad67 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -2348,7 +2348,6 @@ errdetail_params(ParamListInfo params)
 			Oid			typoutput;
 			bool		typisvarlena;
 			char	   *pstring;
-			char	   *p;
 
 			appendStringInfo(&param_str, "%s$%d = ",
 							 paramno > 0 ? ", " : "",
@@ -2364,14 +2363,7 @@ errdetail_params(ParamListInfo params)
 
 			pstring = OidOutputFunctionCall(typoutput, prm->value);
 
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
+			appendStringInfoStringQuoted(&param_str, pstring);
 
 			pfree(pstring);
 		}
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
index a50e587da9..f4dddf8223 100644
--- a/src/common/stringinfo.c
+++ b/src/common/stringinfo.c
@@ -178,6 +178,46 @@ appendStringInfoString(StringInfo str, const char *s)
 	appendBinaryStringInfo(str, s, strlen(s));
 }
 
+/*
+ * appendStringInfoStringQuoted
+ *
+ * Append a null-terminated string to str, adding single quotes around it
+ * and doubling all single quotes.
+ */
+void
+appendStringInfoStringQuoted(StringInfo str, const char *s)
+{
+	const char *chunk_search_start = s,
+			   *chunk_copy_start = s,
+			   *chunk_end;
+	int			len;
+
+	Assert(str != NULL);
+
+	appendStringInfoCharMacro(str, '\'');
+
+	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
+	{
+		/* copy including the found delimiting ' */
+		appendBinaryStringInfoNT(str,
+								 chunk_copy_start,
+								 chunk_end - chunk_copy_start + 1);
+
+		/* in order to double it, include this ' into the next chunk as well */
+		chunk_copy_start = chunk_end;
+		chunk_search_start = chunk_end + 1;
+	}
+
+	/* copy the last chunk, ensuring sufficient space for final bytes */
+	len = strlen(chunk_copy_start);
+	enlargeStringInfo(str, len + 2);
+	appendBinaryStringInfoNT(str, chunk_copy_start, len);
+
+	/* add terminators */
+	appendStringInfoCharMacro(str, '\'');
+	str->data[str->len] = '\0';
+}
+
 /*
  * appendStringInfoChar
  *
diff --git a/src/include/lib/stringinfo.h b/src/include/lib/stringinfo.h
index e27942728e..7de2773e1f 100644
--- a/src/include/lib/stringinfo.h
+++ b/src/include/lib/stringinfo.h
@@ -113,6 +113,13 @@ extern int	appendStringInfoVA(StringInfo str, const char *fmt, va_list args) pg_
  */
 extern void appendStringInfoString(StringInfo str, const char *s);
 
+/*------------------------
+ * appendStringInfoStringQuoted
+ * Append a null-terminated string to str, adding single quotes around it
+ * and doubling all single quotes.
+ */
+extern void appendStringInfoStringQuoted(StringInfo str, const char *s);
+
 /*------------------------
  * appendStringInfoChar
  * Append a single byte to str.
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 4f0de7a811..23553a6948 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -8611,19 +8611,10 @@ format_expr_params(PLpgSQL_execstate *estate,
 		if (paramisnull)
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, paramdatum, paramtypeid);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 paramdatum,
+																 paramtypeid));
 
 		paramno++;
 	}
@@ -8661,19 +8652,10 @@ format_preparedparamsdata(PLpgSQL_execstate *estate,
 		if (ppd->nulls[paramno] == 'n')
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, ppd->values[paramno], ppd->types[paramno]);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 ppd->values[paramno],
+																 ppd->types[paramno]));
 	}
 
 	MemoryContextSwitchTo(oldcontext);
-- 
2.20.1

From 850fb629ca2fa9de0868469ba9a122780462ce0f Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Mon, 2 Dec 2019 16:02:48 -0300
Subject: [PATCH v15 2/2] bashtanov v14

---
 doc/src/sgml/config.sgml                      |  23 +++
 src/backend/nodes/params.c                    | 125 ++++++++++++
 src/backend/tcop/postgres.c                   | 101 ++++-----
 src/backend/utils/misc/guc.c                  |  10 +
 src/backend/utils/misc/postgresql.conf.sample |   1 +
 src/include/nodes/params.h                    |   3 +
 src/include/utils/guc.h                       |   1 +
 src/test/README                               |   3 +-
 src/test/examples/.gitignore                  |   1 +
 src/test/examples/Makefile                    |   2 +-
 src/test/examples/testlibpq5.c                | 193 ++++++++++++++++++
 11 files changed, 413 insertions(+), 50 deletions(-)
 create mode 100644 src/test/examples/testlibpq5.c

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 53ac14490a..5d1c90282f 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6595,6 +6595,29 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether bind parameters are logged when a statement is logged
+        as a result of <xref linkend="guc-log-min-error-statement"/>.
+        It adds some overhead, as postgres will compute and store textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged.
+        This setting has no effect on statements logged due to
+        <xref linkend="guc-log-min-duration-statement"/> or
+        <xref linkend="guc-log-statement"/> settings, as they are always logged
+        with parameters.
+        The default is <literal>off</literal>.
+        Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index cf4387e40f..dd0402a968 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -15,11 +15,14 @@
 
 #include "postgres.h"
 
+#include "lib/stringinfo.h"
 #include "nodes/bitmapset.h"
 #include "nodes/params.h"
 #include "storage/shmem.h"
 #include "utils/datum.h"
+#include "utils/guc.h"
 #include "utils/lsyscache.h"
+#include "utils/memutils.h"
 
 
 /*
@@ -44,6 +47,7 @@ makeParamList(int numParams)
 	retval->paramCompileArg = NULL;
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
+	retval->paramValuesStr = NULL;
 	retval->numParams = numParams;
 
 	return retval;
@@ -58,6 +62,8 @@ makeParamList(int numParams)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * paramValuesStr is not copied, either.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -221,6 +227,8 @@ SerializeParamList(ParamListInfo paramLI, char **start_address)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * paramValuesStr is not copied.
  */
 ParamListInfo
 RestoreParamList(char **start_address)
@@ -251,3 +259,120 @@ RestoreParamList(char **start_address)
 
 	return paramLI;
 }
+
+/*
+ * BuildParamLogString - create a string to represent parameters list for
+ * logging and save it to params. If caller already knows textual
+ * representations for some or all parameters, it can pass an array of exactly
+ * params->numParams values as knownTextValues. It can contain NULLs for the
+ * individual values not known, or, if no text text values known at all the
+ * caller may pass NULL pointer.
+ */
+void
+BuildParamLogString(ParamListInfo params, char **knownTextValues)
+{
+	MemoryContext tmpCxt,
+				oldCxt;
+	int			paramStringLen = 0;
+	StringInfoData buf;
+	char	  **textValues;
+
+	/*
+	 * nothing to do if it's is already set; also, no work if the param fetch
+	 * hook is in use.
+	 *
+	 * XXX invoke the fetch hook to obtain the value? (probably useless)
+	 */
+	if (params->paramValuesStr != NULL ||
+		params->paramFetch != NULL)
+		return;
+
+	initStringInfo(&buf);
+
+	tmpCxt = AllocSetContextCreate(CurrentMemoryContext,
+								   "BuildParamLogString",
+								   ALLOCSET_DEFAULT_SIZES);
+	oldCxt = MemoryContextSwitchTo(tmpCxt);
+
+	textValues = (char **) palloc0(params->numParams * sizeof(char *));
+
+	/* calculate unknown text representations and pre-calculate byte lengths */
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData param = params->params[paramno];
+
+		/* add space for the param number of digits XXX slooow? */
+		for (int d = paramno + 1; d > 0; d /= 10)
+			paramStringLen++;
+
+		if (param.isnull)
+		{
+			paramStringLen += 4;	/* for "NULL" */
+		}
+		else
+		{
+			/* find out textValues[paramno] */
+			if (knownTextValues != NULL && knownTextValues[paramno] != NULL)
+			{
+				textValues[paramno] = knownTextValues[paramno];
+			}
+			else
+			{
+				Oid			typoutput;
+				bool		typisvarlena;
+
+				getTypeOutputInfo(param.ptype, &typoutput, &typisvarlena);
+				textValues[paramno] = OidOutputFunctionCall(typoutput,
+															param.value);
+			}
+
+			/* Count the length of the text value itself */
+			paramStringLen += strlen(textValues[paramno]);
+		}
+	}
+
+	/*-----------------------------
+	 * The output for each datum looks like this:
+	 * "$1 = something, "
+	 *  ^ ^^^         ^^
+	 * except for the last datum where we need \0 instead of ", ".
+	 *-----------------------------
+	 */
+	paramStringLen += params->numParams * 6 - 1;
+
+	MemoryContextSwitchTo(oldCxt);
+
+	/* enlarge at once to avoid multiple reallocations */
+	enlargeStringInfo(&buf, paramStringLen);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		appendStringInfo(&buf,
+						 "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+		appendStringInfoStringQuoted(&buf, textValues[paramno]);
+	}
+
+	params->paramValuesStr = buf.data;
+
+	MemoryContextDelete(tmpCxt);
+}
+
+/*
+ * ParamsErrorCallback - callback for printing parameters in error context
+ */
+void
+ParamsErrorCallback(void *arg)
+{
+	ParamListInfo params = (ParamListInfo) arg;
+
+	if (params == NULL || params->paramValuesStr == NULL)
+		return;
+
+	/*
+	 * XXX this clobbers any other DETAIL line that the error callsite could
+	 * have had.  Do we care?
+	 */
+	errdetail_log("parameters: %s", params->paramValuesStr);
+}
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 0bff20ad67..ef8eda6de8 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -1613,6 +1613,7 @@ exec_bind_message(StringInfo input_message)
 	bool		save_log_statement_stats = log_statement_stats;
 	bool		snapshot_set = false;
 	char		msec_str[32];
+	ErrorContextCallback params_errcxt;
 
 	/* Get the fixed part of the message */
 	portal_name = pq_getmsgstring(input_message);
@@ -1752,6 +1753,8 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		char	  **knownTextValues = NULL;
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1819,9 +1822,26 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				/*
+				 * Save the parameter string if we need it; otherwise free it.
+				 */
+				if (pstring)
+				{
+					if (log_parameters_on_error)
+					{
+						/*
+						 * Allocate this on first use, making sure to put it
+						 * in a short-lived context.
+						 */
+						if (knownTextValues == NULL)
+							knownTextValues =
+								MemoryContextAllocZero(MessageContext,
+													   numParams * sizeof(char *));
+						knownTextValues[paramno] = pstring;
+					}
+					else if (pstring != pbuf.data)
+						pfree(pstring);
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1871,6 +1891,9 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		if (log_parameters_on_error)
+			BuildParamLogString(params, knownTextValues);
 	}
 	else
 		params = NULL;
@@ -1878,6 +1901,12 @@ exec_bind_message(StringInfo input_message)
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
+	/* Set the error callback so that parameters are logged, as needed  */
+	params_errcxt.previous = error_context_stack;
+	params_errcxt.callback = ParamsErrorCallback;
+	params_errcxt.arg = (void *) params;
+	error_context_stack = &params_errcxt;
+
 	/* Get the result format codes */
 	numRFormats = pq_getmsgint(input_message, 2);
 	if (numRFormats > 0)
@@ -1923,6 +1952,12 @@ exec_bind_message(StringInfo input_message)
 	 */
 	PortalSetResultFormat(portal, numRFormats, rformats);
 
+	/*
+	 * Done binding; remove the parameters error callback.  Entries emitted
+	 * later determine independently whether to log the parameters or not.
+	 */
+	error_context_stack = error_context_stack->previous;
+
 	/*
 	 * Send BindComplete.
 	 */
@@ -1979,6 +2014,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 	bool		execute_is_fetch;
 	bool		was_logged = false;
 	char		msec_str[32];
+	ErrorContextCallback params_errcxt;
 
 	/* Adjust destination to tell printtup.c what to do */
 	dest = whereToSendOutput;
@@ -2103,8 +2139,14 @@ exec_execute_message(const char *portal_name, long max_rows)
 	CHECK_FOR_INTERRUPTS();
 
 	/*
-	 * Okay to run the portal.
+	 * Okay to run the portal.  Set the error callback so that parameters are
+	 * logged, as needed.
 	 */
+	params_errcxt.previous = error_context_stack;
+	params_errcxt.callback = ParamsErrorCallback;
+	params_errcxt.arg = (void *) portalParams;
+	error_context_stack = &params_errcxt;
+
 	if (max_rows <= 0)
 		max_rows = FETCH_ALL;
 
@@ -2118,6 +2160,9 @@ exec_execute_message(const char *portal_name, long max_rows)
 
 	receiver->rDestroy(receiver);
 
+	/* Done executing; remove the params error callback */
+	error_context_stack = error_context_stack->previous;
+
 	if (completed)
 	{
 		if (is_xact_command)
@@ -2328,51 +2373,13 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
+	if (params && params->numParams > 0)
 	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
+		BuildParamLogString(params, NULL);
 
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoStringQuoted(&param_str, pstring);
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
-
-		pfree(param_str.data);
-
-		MemoryContextSwitchTo(oldcontext);
+		if (params->paramValuesStr &&
+			params->paramValuesStr[0] != '\0')
+			errdetail("parameters: %s", params->paramValuesStr);
 	}
 
 	return 0;
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index ba74bf9f7d..8d951ce404 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -486,6 +486,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1300,6 +1301,15 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
+	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
 	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 9541879c1f..087190ce63 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -544,6 +544,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd9046619c..ba51dfe5e0 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -115,6 +115,7 @@ typedef struct ParamListInfoData
 	void	   *paramCompileArg;
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
+	char	   *paramValuesStr;		/* params as a single string for errors */
 	int			numParams;		/* nominal/maximum # of Params represented */
 
 	/*
@@ -156,5 +157,7 @@ extern ParamListInfo copyParamList(ParamListInfo from);
 extern Size EstimateParamListSpace(ParamListInfo paramLI);
 extern void SerializeParamList(ParamListInfo paramLI, char **start_address);
 extern ParamListInfo RestoreParamList(char **start_address);
+extern void BuildParamLogString(ParamListInfo params, char **paramTextValues);
+extern void ParamsErrorCallback(void *arg);
 
 #endif							/* PARAMS_H */
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 50098e63fe..41d5e1d14a 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
diff --git a/src/test/README b/src/test/README
index b5ccfc0cf6..22e624d8ba 100644
--- a/src/test/README
+++ b/src/test/README
@@ -12,8 +12,7 @@ authentication/
   Tests for authentication
 
 examples/
-  Demonstration programs for libpq that double as regression tests via
-  "make check"
+  Demonstration programs for libpq that double as regression tests
 
 isolation/
   Tests for concurrent behavior at the SQL level
diff --git a/src/test/examples/.gitignore b/src/test/examples/.gitignore
index 1957ec198f..007aaee590 100644
--- a/src/test/examples/.gitignore
+++ b/src/test/examples/.gitignore
@@ -2,5 +2,6 @@
 /testlibpq2
 /testlibpq3
 /testlibpq4
+/testlibpq5
 /testlo
 /testlo64
diff --git a/src/test/examples/Makefile b/src/test/examples/Makefile
index a67f456904..0407ca60bc 100644
--- a/src/test/examples/Makefile
+++ b/src/test/examples/Makefile
@@ -14,7 +14,7 @@ override CPPFLAGS := -I$(libpq_srcdir) $(CPPFLAGS)
 LDFLAGS_INTERNAL += $(libpq_pgport)
 
 
-PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlo testlo64
+PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlibpq5 testlo testlo64
 
 all: $(PROGS)
 
diff --git a/src/test/examples/testlibpq5.c b/src/test/examples/testlibpq5.c
new file mode 100644
index 0000000000..47a5e31335
--- /dev/null
+++ b/src/test/examples/testlibpq5.c
@@ -0,0 +1,193 @@
+/*
+ * src/test/examples/testlibpq5.c
+ *
+ * testlibpq5.c
+ *		Test logging of statement parameters in case of errors.
+ */
+
+#ifdef WIN32
+#include <windows.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/types.h>
+#include "libpq-fe.h"
+
+static void
+exit_nicely(PGconn *conn)
+{
+	PQfinish(conn);
+	exit(1);
+}
+
+int
+main(int argc, char **argv)
+{
+	const char *conninfo;
+	PGconn	   *conn;
+	PGresult   *res;
+	const char *paramValues[3];
+	int			paramLengths[3];
+	int			paramFormats[3];
+	uint32_t	binaryIntVal;
+
+	/*
+	 * If the user supplies a parameter on the command line, use it as the
+	 * conninfo string; otherwise default to setting dbname=postgres and using
+	 * environment variables or defaults for all other connection parameters.
+	 */
+	if (argc > 1)
+		conninfo = argv[1];
+	else
+		conninfo = "dbname = postgres";
+
+	/* Make a connection to the database */
+	conn = PQconnectdb(conninfo);
+
+	/* Check to see that the backend connection was successfully made */
+	if (PQstatus(conn) != CONNECTION_OK)
+	{
+		fprintf(stderr, "Connection to database failed: %s",
+				PQerrorMessage(conn));
+		exit_nicely(conn);
+	}
+
+	/* Set always-secure search path, so malicious users can't take control. */
+	res = PQexec(conn,
+				 "SELECT pg_catalog.set_config('search_path', '', false)");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/*
+	 * Transmit parameters in different forms and make a statement fail.  User
+	 * can then verify the server log.
+	 */
+	res = PQexec(conn, "SET log_parameters_on_error = on");
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/* emit error on parse stage */
+	paramValues[0] = (char *) "non-number -- parse";
+	paramLengths[0] = strlen(paramValues[2]) + 1;
+	paramFormats[0] = 0;		/* text */
+	res = PQexecParams(conn,
+					   "SELECT $1::int",
+					   1,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("text->int conversion error expected on parse stage, "
+		   "got an error message from server: %s\n",
+		   PQerrorMessage(conn));
+
+	/* emit error on bind stage */
+	paramValues[0] = (char *) "{malformed json -- bind :-{";
+	paramLengths[0] = strlen(paramValues[2]) + 1;
+	paramFormats[0] = 0;		/* text */
+	res = PQexecParams(conn,
+					   "SELECT (' ' || $1::text || ' ')::json",
+					   1,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Json parsing error expected on bind stage, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* divide by zero -- but server won't realize until execution; 0 params */
+	res = PQexecParams(conn,
+					   "SELECT 1 / (random() / 2)::int /*exec*/",
+					   0,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   NULL,
+					   NULL,
+					   NULL,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero on execution expected, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* divide by zero -- but server won't realize until execution; 3 params */
+	paramValues[0] = (char *) &binaryIntVal;
+	paramLengths[0] = sizeof(binaryIntVal);
+	paramFormats[0] = 1;		/* binary */
+	paramValues[1] = "2";
+	paramLengths[1] = strlen(paramValues[1]) + 1;
+	paramFormats[1] = 0;		/* text */
+	paramValues[2] = (char *) "everyone's little $$ in \"dollar\"";
+	paramLengths[2] = strlen(paramValues[2]) + 1;
+	paramFormats[2] = 0;		/* text */
+	res = PQexecParams(
+		conn,
+		"SELECT 1 / (random() / 2)::int + $1::int + $2::int, $3::text /*exec*/",
+		3,		/* # params */
+		NULL,	/* let the backend deduce param type */
+		paramValues,
+		paramLengths,
+		paramFormats,
+		1		/* ask for binary results */
+	);
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero on execution expected, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* close the connection to the database and cleanup */
+	PQfinish(conn);
+
+	return 0;
+}
-- 
2.20.1

From 1c5ffb2fb828a3589564d2f8af828e1be0549956 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Tue, 3 Dec 2019 10:08:35 -0300
Subject: [PATCH v16 1/2] Add appendStringInfoStringQuoted
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Simplifies some coding that prints parameters, as well as optimize to do
it per non-quote chunks instead of per byte.

Author: Alexey Bashtanov and Álvaro Herrera, after a suggestion from Andres Freund
Discussion: https://postgr.es/m/20190920203905.xkv5udsd5dxfs6tr@alap3.anarazel.de
---
 src/backend/tcop/postgres.c  | 10 +--------
 src/common/stringinfo.c      | 40 ++++++++++++++++++++++++++++++++++++
 src/include/lib/stringinfo.h |  7 +++++++
 src/pl/plpgsql/src/pl_exec.c | 34 ++++++++----------------------
 4 files changed, 56 insertions(+), 35 deletions(-)

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3b85e48333..0bff20ad67 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -2348,7 +2348,6 @@ errdetail_params(ParamListInfo params)
 			Oid			typoutput;
 			bool		typisvarlena;
 			char	   *pstring;
-			char	   *p;
 
 			appendStringInfo(&param_str, "%s$%d = ",
 							 paramno > 0 ? ", " : "",
@@ -2364,14 +2363,7 @@ errdetail_params(ParamListInfo params)
 
 			pstring = OidOutputFunctionCall(typoutput, prm->value);
 
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
+			appendStringInfoStringQuoted(&param_str, pstring);
 
 			pfree(pstring);
 		}
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
index a50e587da9..f4dddf8223 100644
--- a/src/common/stringinfo.c
+++ b/src/common/stringinfo.c
@@ -178,6 +178,46 @@ appendStringInfoString(StringInfo str, const char *s)
 	appendBinaryStringInfo(str, s, strlen(s));
 }
 
+/*
+ * appendStringInfoStringQuoted
+ *
+ * Append a null-terminated string to str, adding single quotes around it
+ * and doubling all single quotes.
+ */
+void
+appendStringInfoStringQuoted(StringInfo str, const char *s)
+{
+	const char *chunk_search_start = s,
+			   *chunk_copy_start = s,
+			   *chunk_end;
+	int			len;
+
+	Assert(str != NULL);
+
+	appendStringInfoCharMacro(str, '\'');
+
+	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
+	{
+		/* copy including the found delimiting ' */
+		appendBinaryStringInfoNT(str,
+								 chunk_copy_start,
+								 chunk_end - chunk_copy_start + 1);
+
+		/* in order to double it, include this ' into the next chunk as well */
+		chunk_copy_start = chunk_end;
+		chunk_search_start = chunk_end + 1;
+	}
+
+	/* copy the last chunk, ensuring sufficient space for final bytes */
+	len = strlen(chunk_copy_start);
+	enlargeStringInfo(str, len + 2);
+	appendBinaryStringInfoNT(str, chunk_copy_start, len);
+
+	/* add terminators */
+	appendStringInfoCharMacro(str, '\'');
+	str->data[str->len] = '\0';
+}
+
 /*
  * appendStringInfoChar
  *
diff --git a/src/include/lib/stringinfo.h b/src/include/lib/stringinfo.h
index e27942728e..7de2773e1f 100644
--- a/src/include/lib/stringinfo.h
+++ b/src/include/lib/stringinfo.h
@@ -113,6 +113,13 @@ extern int	appendStringInfoVA(StringInfo str, const char *fmt, va_list args) pg_
  */
 extern void appendStringInfoString(StringInfo str, const char *s);
 
+/*------------------------
+ * appendStringInfoStringQuoted
+ * Append a null-terminated string to str, adding single quotes around it
+ * and doubling all single quotes.
+ */
+extern void appendStringInfoStringQuoted(StringInfo str, const char *s);
+
 /*------------------------
  * appendStringInfoChar
  * Append a single byte to str.
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 4f0de7a811..23553a6948 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -8611,19 +8611,10 @@ format_expr_params(PLpgSQL_execstate *estate,
 		if (paramisnull)
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, paramdatum, paramtypeid);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 paramdatum,
+																 paramtypeid));
 
 		paramno++;
 	}
@@ -8661,19 +8652,10 @@ format_preparedparamsdata(PLpgSQL_execstate *estate,
 		if (ppd->nulls[paramno] == 'n')
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, ppd->values[paramno], ppd->types[paramno]);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 ppd->values[paramno],
+																 ppd->types[paramno]));
 	}
 
 	MemoryContextSwitchTo(oldcontext);
-- 
2.20.1

From fcbe0a5501271a5fa7b0e3f8611ae2ee896155af Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Mon, 2 Dec 2019 16:02:48 -0300
Subject: [PATCH v16 2/2] Emit parameter values during query bind/execute
 errors

---
 doc/src/sgml/config.sgml                      |  23 +++
 src/backend/nodes/params.c                    | 121 +++++++++++
 src/backend/tcop/postgres.c                   | 102 ++++-----
 src/backend/utils/misc/guc.c                  |  10 +
 src/backend/utils/misc/postgresql.conf.sample |   1 +
 src/include/nodes/params.h                    |   3 +
 src/include/utils/guc.h                       |   1 +
 src/test/README                               |   3 +-
 src/test/examples/.gitignore                  |   1 +
 src/test/examples/Makefile                    |   2 +-
 src/test/examples/testlibpq5.c                | 193 ++++++++++++++++++
 11 files changed, 410 insertions(+), 50 deletions(-)
 create mode 100644 src/test/examples/testlibpq5.c

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 53ac14490a..5d1c90282f 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6595,6 +6595,29 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether bind parameters are logged when a statement is logged
+        as a result of <xref linkend="guc-log-min-error-statement"/>.
+        It adds some overhead, as postgres will compute and store textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged.
+        This setting has no effect on statements logged due to
+        <xref linkend="guc-log-min-duration-statement"/> or
+        <xref linkend="guc-log-statement"/> settings, as they are always logged
+        with parameters.
+        The default is <literal>off</literal>.
+        Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index cf4387e40f..13d90f6551 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -15,11 +15,14 @@
 
 #include "postgres.h"
 
+#include "access/xact.h"
+#include "lib/stringinfo.h"
 #include "nodes/bitmapset.h"
 #include "nodes/params.h"
 #include "storage/shmem.h"
 #include "utils/datum.h"
 #include "utils/lsyscache.h"
+#include "utils/memutils.h"
 
 
 /*
@@ -44,6 +47,7 @@ makeParamList(int numParams)
 	retval->paramCompileArg = NULL;
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
+	retval->paramValuesStr = NULL;
 	retval->numParams = numParams;
 
 	return retval;
@@ -58,6 +62,8 @@ makeParamList(int numParams)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * paramValuesStr is not copied, either.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -221,6 +227,8 @@ SerializeParamList(ParamListInfo paramLI, char **start_address)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * paramValuesStr is not copied.
  */
 ParamListInfo
 RestoreParamList(char **start_address)
@@ -251,3 +259,116 @@ RestoreParamList(char **start_address)
 
 	return paramLI;
 }
+
+/*
+ * BuildParamLogString
+ *		Prepare for reporting parameter values.
+ *
+ * Create a string to represent parameters list for logging and save it to
+ * params. If caller already knows textual representations for some or all
+ * parameters, it can pass an array of exactly params->numParams values as
+ * knownTextValues. It can contain NULLs for the individual values not known,
+ * or, if no text text values known at all the caller may pass NULL pointer.
+ *
+ * This should only be called if log_parameters_on_error is set, or caller
+ * wants to report the query parameters for other reasons.
+ */
+void
+BuildParamLogString(ParamListInfo params, char **knownTextValues)
+{
+	MemoryContext tmpCxt,
+				oldCxt;
+	StringInfoData buf;
+
+	/*
+	 * Nothing to do if it's is already set; also, no work if the param fetch
+	 * hook is in use.  (Mostly because it's unimplemented ... but that's
+	 * because it doesn't seem a case worth pursuing.)  Also, avoid calling
+	 * user-defined I/O functions when in an aborted transaction.  It might
+	 * be possible to improve on this when some knownTextValues exist.
+	 */
+	if (params->paramValuesStr != NULL ||
+		params->paramFetch != NULL ||
+		IsAbortedTransactionBlockState())
+		return;
+
+	/*
+	 * Initialize the output stringinfo, in the callers memory context.
+	 *
+	 * To avoid repeated stringinfo enlargement, we assume 64 bytes per param
+	 * for the first 128 params, then 16 bytes for each until completing 1024.
+	 * Add zero bytes for parameters beyond 1024, since things are difficult
+	 * to anticipate at that point.  Note that because stringinfo initial size
+	 * is 1024, we don't have to do anything with 8 parameters or less.
+	 *
+	 * (It doesn't seem worth the time or code complication to strlen() each
+	 * parameter individually.)
+	 */
+	initStringInfo(&buf);
+	if (params->numParams > 8)
+		enlargeStringInfo(&buf,
+						  64 * Min(params->numParams, 128) +
+						  16 * Min(Max(0, params->numParams - 128), 1024 - 128));
+
+	/* Use a temporary context to call output functions, just in case */
+	tmpCxt = AllocSetContextCreate(CurrentMemoryContext,
+								   "BuildParamLogString",
+								   ALLOCSET_SMALL_SIZES);
+	oldCxt = MemoryContextSwitchTo(tmpCxt);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *param = &params->params[paramno];
+
+		appendStringInfo(&buf,
+						 "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (param->isnull || !OidIsValid(param->ptype))
+			appendStringInfoString(&buf, "NULL");
+		else
+		{
+			if (knownTextValues != NULL && knownTextValues[paramno] != NULL)
+				appendStringInfoStringQuoted(&buf, knownTextValues[paramno]);
+			else
+			{
+				Oid			typoutput;
+				bool		typisvarlena;
+				char	   *pstring;
+
+				getTypeOutputInfo(param->ptype, &typoutput, &typisvarlena);
+				pstring = OidOutputFunctionCall(typoutput, param->value);
+				appendStringInfoStringQuoted(&buf, pstring);
+			}
+		}
+
+		MemoryContextReset(tmpCxt);
+	}
+
+	params->paramValuesStr = buf.data;
+
+	MemoryContextSwitchTo(oldCxt);
+	MemoryContextDelete(tmpCxt);
+}
+
+/*
+ * ParamsErrorCallback - callback for printing parameters in error context
+ *
+ * Note that this is a no-op unless BuildParamLogString has been called
+ * beforehand.
+ */
+void
+ParamsErrorCallback(void *arg)
+{
+	ParamListInfo params = (ParamListInfo) arg;
+
+	if (params == NULL || params->paramValuesStr == NULL)
+		return;
+
+	/*
+	 * XXX this clobbers any other DETAIL line that the error callsite could
+	 * have had.  Do we care?
+	 */
+	errdetail("parameters: %s", params->paramValuesStr);
+}
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 0bff20ad67..9a009a5a9b 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -1613,6 +1613,7 @@ exec_bind_message(StringInfo input_message)
 	bool		save_log_statement_stats = log_statement_stats;
 	bool		snapshot_set = false;
 	char		msec_str[32];
+	ErrorContextCallback params_errcxt;
 
 	/* Get the fixed part of the message */
 	portal_name = pq_getmsgstring(input_message);
@@ -1752,6 +1753,8 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		char	  **knownTextValues = NULL;
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1819,9 +1822,26 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				/*
+				 * Save the parameter string if we need it; otherwise free it.
+				 */
+				if (pstring)
+				{
+					if (log_parameters_on_error)
+					{
+						/*
+						 * Allocate this on first use, making sure to put it
+						 * in a short-lived context.
+						 */
+						if (knownTextValues == NULL)
+							knownTextValues =
+								MemoryContextAllocZero(MessageContext,
+													   numParams * sizeof(char *));
+						knownTextValues[paramno] = pstring;
+					}
+					else if (pstring != pbuf.data)
+						pfree(pstring);
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1871,6 +1891,10 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/* Prepare for printing parameters, if configured to do so */
+		if (log_parameters_on_error)
+			BuildParamLogString(params, knownTextValues);
 	}
 	else
 		params = NULL;
@@ -1878,6 +1902,12 @@ exec_bind_message(StringInfo input_message)
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
+	/* Set the error callback so that parameters are logged, as needed  */
+	params_errcxt.previous = error_context_stack;
+	params_errcxt.callback = ParamsErrorCallback;
+	params_errcxt.arg = (void *) params;
+	error_context_stack = &params_errcxt;
+
 	/* Get the result format codes */
 	numRFormats = pq_getmsgint(input_message, 2);
 	if (numRFormats > 0)
@@ -1923,6 +1953,12 @@ exec_bind_message(StringInfo input_message)
 	 */
 	PortalSetResultFormat(portal, numRFormats, rformats);
 
+	/*
+	 * Done binding; remove the parameters error callback.  Entries emitted
+	 * later determine independently whether to log the parameters or not.
+	 */
+	error_context_stack = error_context_stack->previous;
+
 	/*
 	 * Send BindComplete.
 	 */
@@ -1979,6 +2015,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 	bool		execute_is_fetch;
 	bool		was_logged = false;
 	char		msec_str[32];
+	ErrorContextCallback params_errcxt;
 
 	/* Adjust destination to tell printtup.c what to do */
 	dest = whereToSendOutput;
@@ -2103,8 +2140,14 @@ exec_execute_message(const char *portal_name, long max_rows)
 	CHECK_FOR_INTERRUPTS();
 
 	/*
-	 * Okay to run the portal.
+	 * Okay to run the portal.  Set the error callback so that parameters are
+	 * logged.  The parameters must have been saved during the bind phase.
 	 */
+	params_errcxt.previous = error_context_stack;
+	params_errcxt.callback = ParamsErrorCallback;
+	params_errcxt.arg = (void *) portalParams;
+	error_context_stack = &params_errcxt;
+
 	if (max_rows <= 0)
 		max_rows = FETCH_ALL;
 
@@ -2118,6 +2161,9 @@ exec_execute_message(const char *portal_name, long max_rows)
 
 	receiver->rDestroy(receiver);
 
+	/* Done executing; remove the params error callback */
+	error_context_stack = error_context_stack->previous;
+
 	if (completed)
 	{
 		if (is_xact_command)
@@ -2328,51 +2374,13 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
+	if (params && params->numParams > 0)
 	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
+		BuildParamLogString(params, NULL);
 
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoStringQuoted(&param_str, pstring);
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
-
-		pfree(param_str.data);
-
-		MemoryContextSwitchTo(oldcontext);
+		if (params->paramValuesStr &&
+			params->paramValuesStr[0] != '\0')
+			errdetail("parameters: %s", params->paramValuesStr);
 	}
 
 	return 0;
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index ba74bf9f7d..8d951ce404 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -486,6 +486,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1300,6 +1301,15 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
+	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
 	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 9541879c1f..087190ce63 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -544,6 +544,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd9046619c..ba51dfe5e0 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -115,6 +115,7 @@ typedef struct ParamListInfoData
 	void	   *paramCompileArg;
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
+	char	   *paramValuesStr;		/* params as a single string for errors */
 	int			numParams;		/* nominal/maximum # of Params represented */
 
 	/*
@@ -156,5 +157,7 @@ extern ParamListInfo copyParamList(ParamListInfo from);
 extern Size EstimateParamListSpace(ParamListInfo paramLI);
 extern void SerializeParamList(ParamListInfo paramLI, char **start_address);
 extern ParamListInfo RestoreParamList(char **start_address);
+extern void BuildParamLogString(ParamListInfo params, char **paramTextValues);
+extern void ParamsErrorCallback(void *arg);
 
 #endif							/* PARAMS_H */
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 50098e63fe..41d5e1d14a 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
diff --git a/src/test/README b/src/test/README
index b5ccfc0cf6..22e624d8ba 100644
--- a/src/test/README
+++ b/src/test/README
@@ -12,8 +12,7 @@ authentication/
   Tests for authentication
 
 examples/
-  Demonstration programs for libpq that double as regression tests via
-  "make check"
+  Demonstration programs for libpq that double as regression tests
 
 isolation/
   Tests for concurrent behavior at the SQL level
diff --git a/src/test/examples/.gitignore b/src/test/examples/.gitignore
index 1957ec198f..007aaee590 100644
--- a/src/test/examples/.gitignore
+++ b/src/test/examples/.gitignore
@@ -2,5 +2,6 @@
 /testlibpq2
 /testlibpq3
 /testlibpq4
+/testlibpq5
 /testlo
 /testlo64
diff --git a/src/test/examples/Makefile b/src/test/examples/Makefile
index a67f456904..0407ca60bc 100644
--- a/src/test/examples/Makefile
+++ b/src/test/examples/Makefile
@@ -14,7 +14,7 @@ override CPPFLAGS := -I$(libpq_srcdir) $(CPPFLAGS)
 LDFLAGS_INTERNAL += $(libpq_pgport)
 
 
-PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlo testlo64
+PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlibpq5 testlo testlo64
 
 all: $(PROGS)
 
diff --git a/src/test/examples/testlibpq5.c b/src/test/examples/testlibpq5.c
new file mode 100644
index 0000000000..47a5e31335
--- /dev/null
+++ b/src/test/examples/testlibpq5.c
@@ -0,0 +1,193 @@
+/*
+ * src/test/examples/testlibpq5.c
+ *
+ * testlibpq5.c
+ *		Test logging of statement parameters in case of errors.
+ */
+
+#ifdef WIN32
+#include <windows.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/types.h>
+#include "libpq-fe.h"
+
+static void
+exit_nicely(PGconn *conn)
+{
+	PQfinish(conn);
+	exit(1);
+}
+
+int
+main(int argc, char **argv)
+{
+	const char *conninfo;
+	PGconn	   *conn;
+	PGresult   *res;
+	const char *paramValues[3];
+	int			paramLengths[3];
+	int			paramFormats[3];
+	uint32_t	binaryIntVal;
+
+	/*
+	 * If the user supplies a parameter on the command line, use it as the
+	 * conninfo string; otherwise default to setting dbname=postgres and using
+	 * environment variables or defaults for all other connection parameters.
+	 */
+	if (argc > 1)
+		conninfo = argv[1];
+	else
+		conninfo = "dbname = postgres";
+
+	/* Make a connection to the database */
+	conn = PQconnectdb(conninfo);
+
+	/* Check to see that the backend connection was successfully made */
+	if (PQstatus(conn) != CONNECTION_OK)
+	{
+		fprintf(stderr, "Connection to database failed: %s",
+				PQerrorMessage(conn));
+		exit_nicely(conn);
+	}
+
+	/* Set always-secure search path, so malicious users can't take control. */
+	res = PQexec(conn,
+				 "SELECT pg_catalog.set_config('search_path', '', false)");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/*
+	 * Transmit parameters in different forms and make a statement fail.  User
+	 * can then verify the server log.
+	 */
+	res = PQexec(conn, "SET log_parameters_on_error = on");
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/* emit error on parse stage */
+	paramValues[0] = (char *) "non-number -- parse";
+	paramLengths[0] = strlen(paramValues[2]) + 1;
+	paramFormats[0] = 0;		/* text */
+	res = PQexecParams(conn,
+					   "SELECT $1::int",
+					   1,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("text->int conversion error expected on parse stage, "
+		   "got an error message from server: %s\n",
+		   PQerrorMessage(conn));
+
+	/* emit error on bind stage */
+	paramValues[0] = (char *) "{malformed json -- bind :-{";
+	paramLengths[0] = strlen(paramValues[2]) + 1;
+	paramFormats[0] = 0;		/* text */
+	res = PQexecParams(conn,
+					   "SELECT (' ' || $1::text || ' ')::json",
+					   1,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Json parsing error expected on bind stage, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* divide by zero -- but server won't realize until execution; 0 params */
+	res = PQexecParams(conn,
+					   "SELECT 1 / (random() / 2)::int /*exec*/",
+					   0,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   NULL,
+					   NULL,
+					   NULL,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero on execution expected, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* divide by zero -- but server won't realize until execution; 3 params */
+	paramValues[0] = (char *) &binaryIntVal;
+	paramLengths[0] = sizeof(binaryIntVal);
+	paramFormats[0] = 1;		/* binary */
+	paramValues[1] = "2";
+	paramLengths[1] = strlen(paramValues[1]) + 1;
+	paramFormats[1] = 0;		/* text */
+	paramValues[2] = (char *) "everyone's little $$ in \"dollar\"";
+	paramLengths[2] = strlen(paramValues[2]) + 1;
+	paramFormats[2] = 0;		/* text */
+	res = PQexecParams(
+		conn,
+		"SELECT 1 / (random() / 2)::int + $1::int + $2::int, $3::text /*exec*/",
+		3,		/* # params */
+		NULL,	/* let the backend deduce param type */
+		paramValues,
+		paramLengths,
+		paramFormats,
+		1		/* ask for binary results */
+	);
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero on execution expected, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* close the connection to the database and cleanup */
+	PQfinish(conn);
+
+	return 0;
+}
-- 
2.20.1

diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index 13d90f6551..a881df578e 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -23,6 +23,7 @@
 #include "utils/datum.h"
 #include "utils/lsyscache.h"
 #include "utils/memutils.h"
+#include "utils/portal.h"
 
 
 /*
@@ -361,14 +362,17 @@ BuildParamLogString(ParamListInfo params, char **knownTextValues)
 void
 ParamsErrorCallback(void *arg)
 {
-	ParamListInfo params = (ParamListInfo) arg;
+	ParamsErrorCbData *data = (ParamsErrorCbData *) arg;
 
-	if (params == NULL || params->paramValuesStr == NULL)
+	if (data == NULL ||
+		data->params == NULL ||
+		data->params->paramValuesStr == NULL)
 		return;
 
-	/*
-	 * XXX this clobbers any other DETAIL line that the error callsite could
-	 * have had.  Do we care?
-	 */
-	errdetail("parameters: %s", params->paramValuesStr);
+	if (data->portalName && data->portalName[0] != '\0')
+		errcontext("extended query \"%s\" with parameters: %s",
+				   data->portalName, data->params->paramValuesStr);
+	else
+		errcontext("extended query with parameters: %s",
+				   data->params->paramValuesStr);
 }
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 9a009a5a9b..05a03ae924 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -1753,7 +1753,7 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
-		char	  **knownTextValues = NULL;
+		char	  **knownTextValues = NULL;	/* allocate on first use */
 
 		params = makeParamList(numParams);
 
@@ -1822,22 +1822,19 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/*
-				 * Save the parameter string if we need it; otherwise free it.
-				 */
+				/* When logging params, save a copy for later. */
 				if (pstring)
 				{
 					if (log_parameters_on_error)
 					{
-						/*
-						 * Allocate this on first use, making sure to put it
-						 * in a short-lived context.
-						 */
 						if (knownTextValues == NULL)
 							knownTextValues =
 								MemoryContextAllocZero(MessageContext,
 													   numParams * sizeof(char *));
-						knownTextValues[paramno] = pstring;
+						knownTextValues[paramno] =
+							pstring == pbuf.data ?
+							MemoryContextStrdup(MessageContext, pstring) :
+							pstring;
 					}
 					else if (pstring != pbuf.data)
 						pfree(pstring);
@@ -1905,7 +1902,8 @@ exec_bind_message(StringInfo input_message)
 	/* Set the error callback so that parameters are logged, as needed  */
 	params_errcxt.previous = error_context_stack;
 	params_errcxt.callback = ParamsErrorCallback;
-	params_errcxt.arg = (void *) params;
+	params_errcxt.arg = (void *) &((ParamsErrorCbData)
+								   { portal->name, params });
 	error_context_stack = &params_errcxt;
 
 	/* Get the result format codes */
@@ -2145,7 +2143,8 @@ exec_execute_message(const char *portal_name, long max_rows)
 	 */
 	params_errcxt.previous = error_context_stack;
 	params_errcxt.callback = ParamsErrorCallback;
-	params_errcxt.arg = (void *) portalParams;
+	params_errcxt.arg = (void *) &((ParamsErrorCbData)
+								   { portal->name, portalParams });
 	error_context_stack = &params_errcxt;
 
 	if (max_rows <= 0)
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index ba51dfe5e0..1e557ca7fd 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -150,6 +150,12 @@ typedef struct ParamExecData
 	bool		isnull;
 } ParamExecData;
 
+/* type of argument for ParamsErrorCallback */
+typedef struct ParamsErrorCbData
+{
+	const char	 *portalName;
+	ParamListInfo params;
+} ParamsErrorCbData;
 
 /* Functions found in src/backend/nodes/params.c */
 extern ParamListInfo makeParamList(int numParams);

From 6e0a777cb51bcb17e15977fbc729fef6b80b3aa8 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Tue, 3 Dec 2019 10:08:35 -0300
Subject: [PATCH v17 1/2] Add appendStringInfoStringQuoted
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Simplifies some coding that prints parameters, as well as optimize to do
it per non-quote chunks instead of per byte.

Author: Alexey Bashtanov and Álvaro Herrera, after a suggestion from Andres Freund
Discussion: https://postgr.es/m/20190920203905.xkv5udsd5dxfs6tr@alap3.anarazel.de
---
 src/backend/tcop/postgres.c           | 10 +---
 src/common/stringinfo.c               | 67 +++++++++++++++++++++++++++
 src/include/lib/stringinfo.h          |  8 ++++
 src/pl/plpgsql/src/pl_exec.c          | 36 ++++----------
 src/test/regress/expected/plpgsql.out | 14 ++++++
 src/test/regress/sql/plpgsql.sql      | 13 ++++++
 6 files changed, 113 insertions(+), 35 deletions(-)

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3b85e48333..3d3172e83d 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -2348,7 +2348,6 @@ errdetail_params(ParamListInfo params)
 			Oid			typoutput;
 			bool		typisvarlena;
 			char	   *pstring;
-			char	   *p;
 
 			appendStringInfo(&param_str, "%s$%d = ",
 							 paramno > 0 ? ", " : "",
@@ -2364,14 +2363,7 @@ errdetail_params(ParamListInfo params)
 
 			pstring = OidOutputFunctionCall(typoutput, prm->value);
 
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
+			appendStringInfoStringQuoted(&param_str, pstring, 0);
 
 			pfree(pstring);
 		}
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
index a50e587da9..6f7555ef96 100644
--- a/src/common/stringinfo.c
+++ b/src/common/stringinfo.c
@@ -178,6 +178,73 @@ appendStringInfoString(StringInfo str, const char *s)
 	appendBinaryStringInfo(str, s, strlen(s));
 }
 
+/*
+ * appendStringInfoStringQuoted
+ *
+ * Append a null-terminated string to str, adding single quotes around it
+ * and doubling all single quotes.
+ */
+void
+appendStringInfoStringQuoted(StringInfo str, const char *s, int maxlen)
+{
+	char	   *copy = NULL;
+	const char *chunk_search_start,
+			   *chunk_copy_start,
+			   *chunk_end;
+	bool		ellipsis;
+
+	Assert(str != NULL);
+
+	if (maxlen > 0)
+	{
+		copy = pnstrdup(s, maxlen);
+		chunk_search_start = copy;
+		chunk_copy_start = copy;
+
+		ellipsis = strnlen(s, maxlen + 1) > maxlen;
+		/* enlarge while we can do so cheaply */
+		enlargeStringInfo(str, maxlen);
+	}
+	else
+	{
+		chunk_search_start = s;
+		chunk_copy_start = s;
+
+		ellipsis = false;
+	}
+
+	appendStringInfoCharMacro(str, '\'');
+
+	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
+	{
+		/* copy including the found delimiting ' */
+		appendBinaryStringInfoNT(str,
+								 chunk_copy_start,
+								 chunk_end - chunk_copy_start + 1);
+
+		/* in order to double it, include this ' into the next chunk as well */
+		chunk_copy_start = chunk_end;
+		chunk_search_start = chunk_end + 1;
+	}
+
+	/* copy the last chunk and terminate */
+	if (ellipsis)
+		appendStringInfo(str, "%s...'", chunk_copy_start);
+	else
+	{
+		int		len = strlen(chunk_copy_start);
+
+		/* ensure sufficient space for terminators */
+		enlargeStringInfo(str, len + 2);
+		appendBinaryStringInfoNT(str, chunk_copy_start, len);
+		appendStringInfoCharMacro(str, '\'');
+		str->data[str->len] = '\0';
+	}
+
+	if (copy)
+		pfree(copy);
+}
+
 /*
  * appendStringInfoChar
  *
diff --git a/src/include/lib/stringinfo.h b/src/include/lib/stringinfo.h
index e27942728e..956ccbba45 100644
--- a/src/include/lib/stringinfo.h
+++ b/src/include/lib/stringinfo.h
@@ -113,6 +113,14 @@ extern int	appendStringInfoVA(StringInfo str, const char *fmt, va_list args) pg_
  */
 extern void appendStringInfoString(StringInfo str, const char *s);
 
+/*------------------------
+ * appendStringInfoStringQuoted
+ * Append a null-terminated string to str, adding single quotes around it
+ * and doubling all single quotes.
+ */
+extern void appendStringInfoStringQuoted(StringInfo str, const char *s,
+										 int maxlen);
+
 /*------------------------
  * appendStringInfoChar
  * Append a single byte to str.
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 4f0de7a811..c3ae409f39 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -8611,19 +8611,11 @@ format_expr_params(PLpgSQL_execstate *estate,
 		if (paramisnull)
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, paramdatum, paramtypeid);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 paramdatum,
+																 paramtypeid),
+										 0);
 
 		paramno++;
 	}
@@ -8661,19 +8653,11 @@ format_preparedparamsdata(PLpgSQL_execstate *estate,
 		if (ppd->nulls[paramno] == 'n')
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, ppd->values[paramno], ppd->types[paramno]);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 ppd->values[paramno],
+																 ppd->types[paramno]),
+										 0);
 	}
 
 	MemoryContextSwitchTo(oldcontext);
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index e85b29455e..cd2c79f4d5 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -2656,6 +2656,20 @@ create or replace function stricttest() returns void as $$
 declare
 x record;
 p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+select stricttest();
+ERROR:  query returned no rows
+DETAIL:  parameters: p1 = '2', p3 = '''Valame Dios!'' dijo Sancho; ''no le dije yo a vuestra merced que mirase bien lo que hacia?'''
+CONTEXT:  PL/pgSQL function stricttest() line 8 at SQL statement
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
 p3 text := 'foo';
 begin
   -- too many rows
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index 70deadfbea..d841d8c0f9 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2280,6 +2280,19 @@ end$$ language plpgsql;
 
 select stricttest();
 
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+
+select stricttest();
+
 create or replace function stricttest() returns void as $$
 declare
 x record;
-- 
2.20.1

From a898bbfb4aefa98325cdd2af9a1b0627c5e7f745 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Mon, 2 Dec 2019 16:02:48 -0300
Subject: [PATCH v17 2/2] Emit parameter values during query bind/execute
 errors

---
 doc/src/sgml/config.sgml                      |  23 +++
 src/backend/nodes/params.c                    | 130 ++++++++++++
 src/backend/tcop/postgres.c                   | 110 +++++-----
 src/backend/utils/misc/guc.c                  |  10 +
 src/backend/utils/misc/postgresql.conf.sample |   1 +
 src/bin/pgbench/t/001_pgbench_with_server.pl  |  35 ++++
 src/include/nodes/params.h                    |  10 +
 src/include/utils/guc.h                       |   1 +
 src/test/README                               |   3 +-
 src/test/examples/.gitignore                  |   1 +
 src/test/examples/Makefile                    |   2 +-
 src/test/examples/testlibpq5.c                | 193 ++++++++++++++++++
 12 files changed, 469 insertions(+), 50 deletions(-)
 create mode 100644 src/test/examples/testlibpq5.c

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 53ac14490a..5d1c90282f 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6595,6 +6595,29 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether bind parameters are logged when a statement is logged
+        as a result of <xref linkend="guc-log-min-error-statement"/>.
+        It adds some overhead, as postgres will compute and store textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged.
+        This setting has no effect on statements logged due to
+        <xref linkend="guc-log-min-duration-statement"/> or
+        <xref linkend="guc-log-statement"/> settings, as they are always logged
+        with parameters.
+        The default is <literal>off</literal>.
+        Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index cf4387e40f..cbdaec9b7c 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -15,11 +15,15 @@
 
 #include "postgres.h"
 
+#include "access/xact.h"
+#include "lib/stringinfo.h"
 #include "nodes/bitmapset.h"
 #include "nodes/params.h"
 #include "storage/shmem.h"
 #include "utils/datum.h"
 #include "utils/lsyscache.h"
+#include "utils/memutils.h"
+#include "utils/portal.h"
 
 
 /*
@@ -44,6 +48,7 @@ makeParamList(int numParams)
 	retval->paramCompileArg = NULL;
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
+	retval->paramValuesStr = NULL;
 	retval->numParams = numParams;
 
 	return retval;
@@ -58,6 +63,8 @@ makeParamList(int numParams)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * paramValuesStr is not copied, either.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -158,6 +165,8 @@ EstimateParamListSpace(ParamListInfo paramLI)
  * RestoreParamList can be used to recreate a ParamListInfo based on the
  * serialized representation; this will be a static, self-contained copy
  * just as copyParamList would create.
+ *
+ * paramValuesStr is not included.
  */
 void
 SerializeParamList(ParamListInfo paramLI, char **start_address)
@@ -251,3 +260,124 @@ RestoreParamList(char **start_address)
 
 	return paramLI;
 }
+
+/*
+ * BuildParamLogString
+ *		Prepare for reporting parameter values.
+ *
+ * Create a string to represent parameters list for logging and save it to
+ * params. If caller already knows textual representations for some or all
+ * parameters, it can pass an array of exactly params->numParams values as
+ * knownTextValues. It can contain NULLs for the individual values not known,
+ * or, if no text text values known at all the caller may pass NULL pointer.
+ *
+ * If valueLen is not zero, that's the maximum number of characters of the
+ * input string printed; an ellipsis is added if more characters exist.
+ * (Added quotes are not considered.)
+ *
+ * This should only be called if log_parameters_on_error is set, or caller
+ * wants to report the query parameters for other reasons.
+ */
+void
+BuildParamLogString(ParamListInfo params, char **knownTextValues, int valueLen)
+{
+	MemoryContext tmpCxt,
+				oldCxt;
+	StringInfoData buf;
+
+	/*
+	 * Nothing to do if it's is already set; also, no work if the param fetch
+	 * hook is in use.  (Mostly because it's unimplemented ... but that's
+	 * because it doesn't seem a case worth pursuing.)  Also, avoid calling
+	 * user-defined I/O functions when in an aborted transaction.  It might
+	 * be possible to improve on this when some knownTextValues exist.
+	 */
+	if (params->paramValuesStr != NULL ||
+		params->paramFetch != NULL ||
+		IsAbortedTransactionBlockState())
+		return;
+
+	/*
+	 * Initialize the output stringinfo, in the callers memory context.
+	 *
+	 * To avoid repeated stringinfo enlargement, we assume 64 bytes per param
+	 * for the first 128 params, then 16 bytes for each until completing 1024.
+	 * Add zero bytes for parameters beyond 1024, since things are difficult
+	 * to anticipate at that point.  Note that because stringinfo initial size
+	 * is 1024, we don't have to do anything with 8 parameters or less.
+	 *
+	 * (It doesn't seem worth the time or code complication to strlen() each
+	 * parameter individually.)
+	 */
+	initStringInfo(&buf);
+	if (params->numParams > 8)
+		enlargeStringInfo(&buf,
+						  64 * Min(params->numParams, 128) +
+						  16 * Min(Max(0, params->numParams - 128), 1024 - 128));
+
+	/* Use a temporary context to call output functions, just in case */
+	tmpCxt = AllocSetContextCreate(CurrentMemoryContext,
+								   "BuildParamLogString",
+								   ALLOCSET_SMALL_SIZES);
+	oldCxt = MemoryContextSwitchTo(tmpCxt);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *param = &params->params[paramno];
+
+		appendStringInfo(&buf,
+						 "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (param->isnull || !OidIsValid(param->ptype))
+			appendStringInfoString(&buf, "NULL");
+		else
+		{
+			if (knownTextValues != NULL && knownTextValues[paramno] != NULL)
+				appendStringInfoStringQuoted(&buf, knownTextValues[paramno],
+											 valueLen);
+			else
+			{
+				Oid			typoutput;
+				bool		typisvarlena;
+				char	   *pstring;
+
+				getTypeOutputInfo(param->ptype, &typoutput, &typisvarlena);
+				pstring = OidOutputFunctionCall(typoutput, param->value);
+				appendStringInfoStringQuoted(&buf, pstring, valueLen);
+			}
+		}
+
+		MemoryContextReset(tmpCxt);
+	}
+
+	params->paramValuesStr = buf.data;
+
+	MemoryContextSwitchTo(oldCxt);
+	MemoryContextDelete(tmpCxt);
+}
+
+/*
+ * ParamsErrorCallback - callback for printing parameters in error context
+ *
+ * Note that this is a no-op unless BuildParamLogString has been called
+ * beforehand.
+ */
+void
+ParamsErrorCallback(void *arg)
+{
+	ParamsErrorCbData *data = (ParamsErrorCbData *) arg;
+
+	if (data == NULL ||
+		data->params == NULL ||
+		data->params->paramValuesStr == NULL)
+		return;
+
+	if (data->portalName && data->portalName[0] != '\0')
+		errcontext("extended query \"%s\" with parameters: %s",
+				   data->portalName, data->params->paramValuesStr);
+	else
+		errcontext("extended query with parameters: %s",
+				   data->params->paramValuesStr);
+}
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3d3172e83d..1d23ec7746 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -1613,6 +1613,7 @@ exec_bind_message(StringInfo input_message)
 	bool		save_log_statement_stats = log_statement_stats;
 	bool		snapshot_set = false;
 	char		msec_str[32];
+	ErrorContextCallback params_errcxt;
 
 	/* Get the fixed part of the message */
 	portal_name = pq_getmsgstring(input_message);
@@ -1752,6 +1753,8 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		char	  **knownTextValues = NULL;	/* allocate on first use */
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1819,9 +1822,28 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				/* When logging params, save a copy for later */
+				if (pstring)
+				{
+					if (log_parameters_on_error)
+					{
+						MemoryContext	oldcxt;
+
+						oldcxt = MemoryContextSwitchTo(MessageContext);
+						if (knownTextValues == NULL)
+							knownTextValues =
+								palloc0(numParams * sizeof(char *));
+						/*
+						 * Note: must copy at least one more byte than
+						 * BuildParamLogString wants to see; otherwise it'll
+						 * fail to include the ellipsis ...
+						 */
+						knownTextValues[paramno] = pnstrdup(pstring, 65);
+						MemoryContextSwitchTo(oldcxt);
+					}
+					if (pstring != pbuf.data)
+						pfree(pstring);
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1871,6 +1893,14 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/*
+		 * Prepare for printing parameters, if configured to do so.  (This is
+		 * saved in the portal, so that they'll appear when the query is
+		 * executed later.)
+		 */
+		if (log_parameters_on_error)
+			BuildParamLogString(params, knownTextValues, 64);
 	}
 	else
 		params = NULL;
@@ -1878,6 +1908,13 @@ exec_bind_message(StringInfo input_message)
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
+	/* Set the error callback so that parameters are logged, as needed  */
+	params_errcxt.previous = error_context_stack;
+	params_errcxt.callback = ParamsErrorCallback;
+	params_errcxt.arg = (void *) &((ParamsErrorCbData)
+								   { portal->name, params });
+	error_context_stack = &params_errcxt;
+
 	/* Get the result format codes */
 	numRFormats = pq_getmsgint(input_message, 2);
 	if (numRFormats > 0)
@@ -1923,6 +1960,12 @@ exec_bind_message(StringInfo input_message)
 	 */
 	PortalSetResultFormat(portal, numRFormats, rformats);
 
+	/*
+	 * Done binding; remove the parameters error callback.  Entries emitted
+	 * later determine independently whether to log the parameters or not.
+	 */
+	error_context_stack = error_context_stack->previous;
+
 	/*
 	 * Send BindComplete.
 	 */
@@ -1979,6 +2022,7 @@ exec_execute_message(const char *portal_name, long max_rows)
 	bool		execute_is_fetch;
 	bool		was_logged = false;
 	char		msec_str[32];
+	ErrorContextCallback params_errcxt;
 
 	/* Adjust destination to tell printtup.c what to do */
 	dest = whereToSendOutput;
@@ -2103,8 +2147,15 @@ exec_execute_message(const char *portal_name, long max_rows)
 	CHECK_FOR_INTERRUPTS();
 
 	/*
-	 * Okay to run the portal.
+	 * Okay to run the portal.  Set the error callback so that parameters are
+	 * logged.  The parameters must have been saved during the bind phase.
 	 */
+	params_errcxt.previous = error_context_stack;
+	params_errcxt.callback = ParamsErrorCallback;
+	params_errcxt.arg = (void *) &((ParamsErrorCbData)
+								   { portal->name, portalParams });
+	error_context_stack = &params_errcxt;
+
 	if (max_rows <= 0)
 		max_rows = FETCH_ALL;
 
@@ -2118,6 +2169,9 @@ exec_execute_message(const char *portal_name, long max_rows)
 
 	receiver->rDestroy(receiver);
 
+	/* Done executing; remove the params error callback */
+	error_context_stack = error_context_stack->previous;
+
 	if (completed)
 	{
 		if (is_xact_command)
@@ -2328,51 +2382,13 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
+	if (params && params->numParams > 0)
 	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
+		BuildParamLogString(params, NULL, 0);
 
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoStringQuoted(&param_str, pstring, 0);
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
-
-		pfree(param_str.data);
-
-		MemoryContextSwitchTo(oldcontext);
+		if (params->paramValuesStr &&
+			params->paramValuesStr[0] != '\0')
+			errdetail("parameters: %s", params->paramValuesStr);
 	}
 
 	return 0;
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index ba74bf9f7d..8d951ce404 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -486,6 +486,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1300,6 +1301,15 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
+	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
 	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 9541879c1f..087190ce63 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -544,6 +544,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/bin/pgbench/t/001_pgbench_with_server.pl b/src/bin/pgbench/t/001_pgbench_with_server.pl
index 1845869016..021d7a1826 100644
--- a/src/bin/pgbench/t/001_pgbench_with_server.pl
+++ b/src/bin/pgbench/t/001_pgbench_with_server.pl
@@ -270,6 +270,41 @@ COMMIT;
 }
 	});
 
+# Verify server logging of parameters
+$node->append_conf('postgresql.conf', "log_parameters_on_error = true");
+$node->reload;
+pgbench(
+		'-n -t1 -c1 -M prepared',
+		2,
+		[],
+		[
+		qr{ERROR:  division by zero},
+		qr{CONTEXT:  extended query with parameters: \$1 = '1', \$2 = NULL}
+		],
+		'server parameter logging',
+		{
+			'001_param_1' => q{select '1' as one \gset
+SELECT 1 / (random() / 2)::int, :one::int, :two::int;
+}
+	});
+
+pgbench(
+		'-n -t1 -c1 -M prepared',
+		2,
+		[],
+		[
+		qr{ERROR:  invalid input syntax for type json},
+		qr[CONTEXT:  JSON data, line 1: \{ invalid\.\.\.
+extended query with parameters: \$1 = '\{ invalid ', \$2 = '''Valame Dios!'' dijo Sancho; ''no le dije yo a vuestra merced que ...'$]m
+		],
+		'server parameter logging',
+		{
+			'001_param_2' => q[select '{ invalid ' as value \gset
+select $$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$$ as long \gset
+select column1::jsonb from (values (:value), (:long)) as q;
+]
+	});
+
 # test expressions
 # command 1..3 and 23 depend on random seed which is used to call srandom.
 pgbench(
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd9046619c..d7a7e1f191 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -115,6 +115,7 @@ typedef struct ParamListInfoData
 	void	   *paramCompileArg;
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
+	char	   *paramValuesStr;		/* params as a single string for errors */
 	int			numParams;		/* nominal/maximum # of Params represented */
 
 	/*
@@ -149,6 +150,12 @@ typedef struct ParamExecData
 	bool		isnull;
 } ParamExecData;
 
+/* type of argument for ParamsErrorCallback */
+typedef struct ParamsErrorCbData
+{
+	const char	 *portalName;
+	ParamListInfo params;
+} ParamsErrorCbData;
 
 /* Functions found in src/backend/nodes/params.c */
 extern ParamListInfo makeParamList(int numParams);
@@ -156,5 +163,8 @@ extern ParamListInfo copyParamList(ParamListInfo from);
 extern Size EstimateParamListSpace(ParamListInfo paramLI);
 extern void SerializeParamList(ParamListInfo paramLI, char **start_address);
 extern ParamListInfo RestoreParamList(char **start_address);
+extern void BuildParamLogString(ParamListInfo params, char **paramTextValues,
+								int valueLen);
+extern void ParamsErrorCallback(void *arg);
 
 #endif							/* PARAMS_H */
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 50098e63fe..41d5e1d14a 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
diff --git a/src/test/README b/src/test/README
index b5ccfc0cf6..22e624d8ba 100644
--- a/src/test/README
+++ b/src/test/README
@@ -12,8 +12,7 @@ authentication/
   Tests for authentication
 
 examples/
-  Demonstration programs for libpq that double as regression tests via
-  "make check"
+  Demonstration programs for libpq that double as regression tests
 
 isolation/
   Tests for concurrent behavior at the SQL level
diff --git a/src/test/examples/.gitignore b/src/test/examples/.gitignore
index 1957ec198f..007aaee590 100644
--- a/src/test/examples/.gitignore
+++ b/src/test/examples/.gitignore
@@ -2,5 +2,6 @@
 /testlibpq2
 /testlibpq3
 /testlibpq4
+/testlibpq5
 /testlo
 /testlo64
diff --git a/src/test/examples/Makefile b/src/test/examples/Makefile
index a67f456904..0407ca60bc 100644
--- a/src/test/examples/Makefile
+++ b/src/test/examples/Makefile
@@ -14,7 +14,7 @@ override CPPFLAGS := -I$(libpq_srcdir) $(CPPFLAGS)
 LDFLAGS_INTERNAL += $(libpq_pgport)
 
 
-PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlo testlo64
+PROGS = testlibpq testlibpq2 testlibpq3 testlibpq4 testlibpq5 testlo testlo64
 
 all: $(PROGS)
 
diff --git a/src/test/examples/testlibpq5.c b/src/test/examples/testlibpq5.c
new file mode 100644
index 0000000000..47a5e31335
--- /dev/null
+++ b/src/test/examples/testlibpq5.c
@@ -0,0 +1,193 @@
+/*
+ * src/test/examples/testlibpq5.c
+ *
+ * testlibpq5.c
+ *		Test logging of statement parameters in case of errors.
+ */
+
+#ifdef WIN32
+#include <windows.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/types.h>
+#include "libpq-fe.h"
+
+static void
+exit_nicely(PGconn *conn)
+{
+	PQfinish(conn);
+	exit(1);
+}
+
+int
+main(int argc, char **argv)
+{
+	const char *conninfo;
+	PGconn	   *conn;
+	PGresult   *res;
+	const char *paramValues[3];
+	int			paramLengths[3];
+	int			paramFormats[3];
+	uint32_t	binaryIntVal;
+
+	/*
+	 * If the user supplies a parameter on the command line, use it as the
+	 * conninfo string; otherwise default to setting dbname=postgres and using
+	 * environment variables or defaults for all other connection parameters.
+	 */
+	if (argc > 1)
+		conninfo = argv[1];
+	else
+		conninfo = "dbname = postgres";
+
+	/* Make a connection to the database */
+	conn = PQconnectdb(conninfo);
+
+	/* Check to see that the backend connection was successfully made */
+	if (PQstatus(conn) != CONNECTION_OK)
+	{
+		fprintf(stderr, "Connection to database failed: %s",
+				PQerrorMessage(conn));
+		exit_nicely(conn);
+	}
+
+	/* Set always-secure search path, so malicious users can't take control. */
+	res = PQexec(conn,
+				 "SELECT pg_catalog.set_config('search_path', '', false)");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/*
+	 * Transmit parameters in different forms and make a statement fail.  User
+	 * can then verify the server log.
+	 */
+	res = PQexec(conn, "SET log_parameters_on_error = on");
+	if (PQresultStatus(res) != PGRES_COMMAND_OK)
+	{
+		fprintf(stderr, "SET failed: %s", PQerrorMessage(conn));
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+
+	/* emit error on parse stage */
+	paramValues[0] = (char *) "non-number -- parse";
+	paramLengths[0] = strlen(paramValues[2]) + 1;
+	paramFormats[0] = 0;		/* text */
+	res = PQexecParams(conn,
+					   "SELECT $1::int",
+					   1,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("text->int conversion error expected on parse stage, "
+		   "got an error message from server: %s\n",
+		   PQerrorMessage(conn));
+
+	/* emit error on bind stage */
+	paramValues[0] = (char *) "{malformed json -- bind :-{";
+	paramLengths[0] = strlen(paramValues[2]) + 1;
+	paramFormats[0] = 0;		/* text */
+	res = PQexecParams(conn,
+					   "SELECT (' ' || $1::text || ' ')::json",
+					   1,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   paramValues,
+					   paramLengths,
+					   paramFormats,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Json parsing error expected on bind stage, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* divide by zero -- but server won't realize until execution; 0 params */
+	res = PQexecParams(conn,
+					   "SELECT 1 / (random() / 2)::int /*exec*/",
+					   0,		/* # params */
+					   NULL,	/* let the backend deduce param type */
+					   NULL,
+					   NULL,
+					   NULL,
+					   1);		/* ask for binary results */
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero on execution expected, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* divide by zero -- but server won't realize until execution; 3 params */
+	paramValues[0] = (char *) &binaryIntVal;
+	paramLengths[0] = sizeof(binaryIntVal);
+	paramFormats[0] = 1;		/* binary */
+	paramValues[1] = "2";
+	paramLengths[1] = strlen(paramValues[1]) + 1;
+	paramFormats[1] = 0;		/* text */
+	paramValues[2] = (char *) "everyone's little $$ in \"dollar\"";
+	paramLengths[2] = strlen(paramValues[2]) + 1;
+	paramFormats[2] = 0;		/* text */
+	res = PQexecParams(
+		conn,
+		"SELECT 1 / (random() / 2)::int + $1::int + $2::int, $3::text /*exec*/",
+		3,		/* # params */
+		NULL,	/* let the backend deduce param type */
+		paramValues,
+		paramLengths,
+		paramFormats,
+		1		/* ask for binary results */
+	);
+
+	if (PQresultStatus(res) != PGRES_FATAL_ERROR)
+	{
+		fprintf(stderr, "SELECT succeeded but was supposed to fail\n");
+		PQclear(res);
+		exit_nicely(conn);
+	}
+	PQclear(res);
+	printf("Division by zero on execution expected, "
+		   "got an error message from server: %s\n"
+		   "Please make sure it has been logged "
+		   "with bind parameters in server log\n",
+		   PQerrorMessage(conn));
+
+	/* close the connection to the database and cleanup */
+	PQfinish(conn);
+
+	return 0;
+}
-- 
2.20.1

From 36f0dc29c1187c49c5072d48796ccbb3369ed8f7 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Tue, 3 Dec 2019 10:08:35 -0300
Subject: [PATCH v18] Add appendStringInfoStringQuoted
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Simplifies some coding that prints parameters, as well as optimize to do
it per non-quote chunks instead of per byte.

This version of the patch makes the new function available to frontends,
and puts wchar.c/encnames.c in libpgport.

Author: Alexey Bashtanov and Álvaro Herrera, after a suggestion from Andres Freund
Discussion: https://postgr.es/m/20190920203905.xkv5udsd5dxfs6tr@alap3.anarazel.de
---
 src/backend/tcop/postgres.c           | 11 +----
 src/backend/utils/mb/mbutils.c        | 31 ------------
 src/backend/utils/mb/wchar.c          | 47 ++++++++++++++++++
 src/common/Makefile                   |  9 +++-
 src/common/stringinfo.c               | 71 +++++++++++++++++++++++++++
 src/include/lib/stringinfo.h          | 10 ++++
 src/pl/plpgsql/src/pl_exec.c          | 39 +++++----------
 src/test/regress/expected/plpgsql.out | 14 ++++++
 src/test/regress/sql/plpgsql.sql      | 13 +++++
 9 files changed, 178 insertions(+), 67 deletions(-)

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3b85e48333..a5e398b2f5 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -2348,7 +2348,6 @@ errdetail_params(ParamListInfo params)
 			Oid			typoutput;
 			bool		typisvarlena;
 			char	   *pstring;
-			char	   *p;
 
 			appendStringInfo(&param_str, "%s$%d = ",
 							 paramno > 0 ? ", " : "",
@@ -2364,14 +2363,8 @@ errdetail_params(ParamListInfo params)
 
 			pstring = OidOutputFunctionCall(typoutput, prm->value);
 
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
+			appendStringInfoStringQuoted(&param_str, GetDatabaseEncoding(),
+										 pstring, 0);
 
 			pfree(pstring);
 		}
diff --git a/src/backend/utils/mb/mbutils.c b/src/backend/utils/mb/mbutils.c
index 6b08b77717..34e9fd9f2c 100644
--- a/src/backend/utils/mb/mbutils.c
+++ b/src/backend/utils/mb/mbutils.c
@@ -865,37 +865,6 @@ pg_mbcliplen(const char *mbstr, int len, int limit)
 								 len, limit);
 }
 
-/*
- * pg_mbcliplen with specified encoding
- */
-int
-pg_encoding_mbcliplen(int encoding, const char *mbstr,
-					  int len, int limit)
-{
-	mblen_converter mblen_fn;
-	int			clen = 0;
-	int			l;
-
-	/* optimization for single byte encoding */
-	if (pg_encoding_max_length(encoding) == 1)
-		return cliplen(mbstr, len, limit);
-
-	mblen_fn = pg_wchar_table[encoding].mblen;
-
-	while (len > 0 && *mbstr)
-	{
-		l = (*mblen_fn) ((const unsigned char *) mbstr);
-		if ((clen + l) > limit)
-			break;
-		clen += l;
-		if (clen == limit)
-			break;
-		len -= l;
-		mbstr += l;
-	}
-	return clen;
-}
-
 /*
  * Similar to pg_mbcliplen except the limit parameter specifies the
  * character length, not the byte length.
diff --git a/src/backend/utils/mb/wchar.c b/src/backend/utils/mb/wchar.c
index b2d598cbee..f0e57593f7 100644
--- a/src/backend/utils/mb/wchar.c
+++ b/src/backend/utils/mb/wchar.c
@@ -14,6 +14,10 @@
 #include "mb/pg_wchar.h"
 
 
+/* Internal functions */
+static int	cliplen(const char *str, int len, int limit);
+
+
 /*
  * Operations on multi-byte encodings are driven by a table of helper
  * functions.
@@ -1861,6 +1865,49 @@ pg_encoding_verifymb(int encoding, const char *mbstr, int len)
 			pg_wchar_table[PG_SQL_ASCII].mbverify((const unsigned char *) mbstr, len));
 }
 
+/* mbcliplen for any single-byte encoding */
+static int
+cliplen(const char *str, int len, int limit)
+{
+	int			l = 0;
+
+	len = Min(len, limit);
+	while (l < len && str[l])
+		l++;
+	return l;
+}
+
+/*
+ * pg_mbcliplen with specified encoding
+ */
+int
+pg_encoding_mbcliplen(int encoding, const char *mbstr,
+					  int len, int limit)
+{
+	mblen_converter mblen_fn;
+	int			clen = 0;
+	int			l;
+
+	/* optimization for single byte encoding */
+	if (pg_encoding_max_length(encoding) == 1)
+		return cliplen(mbstr, len, limit);
+
+	mblen_fn = pg_wchar_table[encoding].mblen;
+
+	while (len > 0 && *mbstr)
+	{
+		l = (*mblen_fn) ((const unsigned char *) mbstr);
+		if ((clen + l) > limit)
+			break;
+		clen += l;
+		if (clen == limit)
+			break;
+		len -= l;
+		mbstr += l;
+	}
+	return clen;
+}
+
 /*
  * fetch maximum length of a given encoding
  */
diff --git a/src/common/Makefile b/src/common/Makefile
index ffb0f6edff..0146918758 100644
--- a/src/common/Makefile
+++ b/src/common/Makefile
@@ -78,6 +78,8 @@ else
 OBJS_COMMON += sha2.o
 endif
 
+backend_src = $(top_srcdir)/src/backend
+
 # A few files are currently only built for frontend, not server
 # (Mkvcbuild.pm has a copy of this list, too)
 OBJS_FRONTEND = \
@@ -85,7 +87,9 @@ OBJS_FRONTEND = \
 	fe_memutils.o \
 	file_utils.o \
 	logging.o \
-	restricted_token.o
+	restricted_token.o \
+	wchar.o \
+	encnames.o
 
 # foo.o, foo_shlib.o, and foo_srv.o are all built from foo.c
 OBJS_SHLIB = $(OBJS_FRONTEND:%.o=%_shlib.o)
@@ -158,6 +162,9 @@ kwlist_d.h: $(top_srcdir)/src/include/parser/kwlist.h $(GEN_KEYWORDLIST_DEPS)
 # that you don't get broken parsing code, even in a non-enable-depend build.
 keywords.o keywords_shlib.o keywords_srv.o: kwlist_d.h
 
+encnames.c wchar.c: % : $(backend_src)/utils/mb/%
+	rm -f $@ && $(LN_S) $< .
+
 # The code imported from Ryu gets a pass on declaration-after-statement,
 # in order to keep it more closely aligned with its upstream.
 RYU_FILES = d2s.o f2s.o
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
index a50e587da9..5198ef97ac 100644
--- a/src/common/stringinfo.c
+++ b/src/common/stringinfo.c
@@ -30,6 +30,7 @@
 #endif
 
 #include "lib/stringinfo.h"
+#include "mb/pg_wchar.h"
 
 
 /*
@@ -178,6 +179,76 @@ appendStringInfoString(StringInfo str, const char *s)
 	appendBinaryStringInfo(str, s, strlen(s));
 }
 
+/*
+ * appendStringInfoStringQuoted
+ *
+ * Append up to maxlen characters from s (which is in the given encoding) to
+ * str, or the whole input string if maxlen <= 0, adding single quotes around
+ * it and doubling all single quotes.  Add an ellipsis if the copy is
+ * incomplete.
+ */
+void
+appendStringInfoStringQuoted(StringInfo str, int encoding, const char *s,
+							 int maxlen)
+{
+	char	   *copy = NULL;
+	const char *chunk_search_start,
+			   *chunk_copy_start,
+			   *chunk_end;
+	bool		ellipsis;
+	int			slen;
+
+	Assert(str != NULL);
+
+	slen = strlen(s);
+	if (maxlen > 0 && maxlen < slen)
+	{
+		int		finallen = pg_encoding_mbcliplen(encoding, s, slen, maxlen);
+
+		copy = pnstrdup(s, finallen);
+		chunk_search_start = copy;
+		chunk_copy_start = copy;
+
+		ellipsis = true;
+	}
+	else
+	{
+		chunk_search_start = s;
+		chunk_copy_start = s;
+
+		ellipsis = false;
+	}
+
+	appendStringInfoCharMacro(str, '\'');
+
+	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
+	{
+		/* copy including the found delimiting ' */
+		appendBinaryStringInfoNT(str,
+								 chunk_copy_start,
+								 chunk_end - chunk_copy_start + 1);
+
+		/* in order to double it, include this ' into the next chunk as well */
+		chunk_copy_start = chunk_end;
+		chunk_search_start = chunk_end + 1;
+	}
+
+	/* copy the last chunk and terminate */
+	if (ellipsis)
+		appendStringInfo(str, "%s...'", chunk_copy_start);
+	else
+	{
+		int		len = strlen(chunk_copy_start);
+
+		/* ensure sufficient space for terminators */
+		appendBinaryStringInfoNT(str, chunk_copy_start, len);
+		appendStringInfoCharMacro(str, '\'');
+	}
+
+	if (copy)
+		pfree(copy);
+}
+
 /*
  * appendStringInfoChar
  *
diff --git a/src/include/lib/stringinfo.h b/src/include/lib/stringinfo.h
index e27942728e..4a2af9e50b 100644
--- a/src/include/lib/stringinfo.h
+++ b/src/include/lib/stringinfo.h
@@ -113,6 +113,16 @@ extern int	appendStringInfoVA(StringInfo str, const char *fmt, va_list args) pg_
  */
 extern void appendStringInfoString(StringInfo str, const char *s);
 
+/*------------------------
+ * appendStringInfoStringQuoted
+ * Append up to maxlen characters from s (which is in the given encoding) to
+ * str, or the whole input string if maxlen <= 0, adding single quotes around
+ * it and doubling all single quotes.  Add an ellipsis if the copy is
+ * incomplete.
+ */
+extern void appendStringInfoStringQuoted(StringInfo str, int encoding,
+										 const char *s, int maxlen);
+
 /*------------------------
  * appendStringInfoChar
  * Append a single byte to str.
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 4f0de7a811..1ba1783490 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -28,6 +28,7 @@
 #include "executor/spi.h"
 #include "executor/spi_priv.h"
 #include "funcapi.h"
+#include "mb/pg_wchar.h"
 #include "miscadmin.h"
 #include "nodes/nodeFuncs.h"
 #include "optimizer/optimizer.h"
@@ -8611,19 +8612,12 @@ format_expr_params(PLpgSQL_execstate *estate,
 		if (paramisnull)
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, paramdatum, paramtypeid);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 GetDatabaseEncoding(),
+										 convert_value_to_string(estate,
+																 paramdatum,
+																 paramtypeid),
+										 0);
 
 		paramno++;
 	}
@@ -8661,19 +8655,12 @@ format_preparedparamsdata(PLpgSQL_execstate *estate,
 		if (ppd->nulls[paramno] == 'n')
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, ppd->values[paramno], ppd->types[paramno]);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 GetDatabaseEncoding(),
+										 convert_value_to_string(estate,
+																 ppd->values[paramno],
+																 ppd->types[paramno]),
+										 0);
 	}
 
 	MemoryContextSwitchTo(oldcontext);
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index e85b29455e..cd2c79f4d5 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -2656,6 +2656,20 @@ create or replace function stricttest() returns void as $$
 declare
 x record;
 p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+select stricttest();
+ERROR:  query returned no rows
+DETAIL:  parameters: p1 = '2', p3 = '''Valame Dios!'' dijo Sancho; ''no le dije yo a vuestra merced que mirase bien lo que hacia?'''
+CONTEXT:  PL/pgSQL function stricttest() line 8 at SQL statement
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
 p3 text := 'foo';
 begin
   -- too many rows
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index 70deadfbea..d841d8c0f9 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2280,6 +2280,19 @@ end$$ language plpgsql;
 
 select stricttest();
 
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+
+select stricttest();
+
 create or replace function stricttest() returns void as $$
 declare
 x record;
-- 
2.20.1

From 817041a46a31ed951d84b6039bd469feea577052 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Tue, 3 Dec 2019 10:08:35 -0300
Subject: [PATCH v19] Add appendStringInfoStringQuoted
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Simplifies some coding that prints parameters, as well as optimize to do
it per non-quote chunks instead of per byte.

Put the new function in a new backend-only file, stringinfo_mb.c.

Author: Alexey Bashtanov and Álvaro Herrera, after a suggestion from Andres Freund
Discussion: https://postgr.es/m/20190920203905.xkv5udsd5dxfs6tr@alap3.anarazel.de
---
 src/backend/tcop/postgres.c           | 10 +--
 src/backend/utils/mb/Makefile         |  1 +
 src/backend/utils/mb/stringinfo_mb.c  | 87 +++++++++++++++++++++++++++
 src/common/stringinfo.c               |  1 +
 src/include/lib/stringinfo.h          | 14 +++++
 src/pl/plpgsql/src/pl_exec.c          | 36 +++--------
 src/test/regress/expected/plpgsql.out | 14 +++++
 src/test/regress/sql/plpgsql.sql      | 13 ++++
 8 files changed, 141 insertions(+), 35 deletions(-)
 create mode 100644 src/backend/utils/mb/stringinfo_mb.c

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3b85e48333..3d3172e83d 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -2348,7 +2348,6 @@ errdetail_params(ParamListInfo params)
 			Oid			typoutput;
 			bool		typisvarlena;
 			char	   *pstring;
-			char	   *p;
 
 			appendStringInfo(&param_str, "%s$%d = ",
 							 paramno > 0 ? ", " : "",
@@ -2364,14 +2363,7 @@ errdetail_params(ParamListInfo params)
 
 			pstring = OidOutputFunctionCall(typoutput, prm->value);
 
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
+			appendStringInfoStringQuoted(&param_str, pstring, 0);
 
 			pfree(pstring);
 		}
diff --git a/src/backend/utils/mb/Makefile b/src/backend/utils/mb/Makefile
index 18dd758cfe..cd4a016449 100644
--- a/src/backend/utils/mb/Makefile
+++ b/src/backend/utils/mb/Makefile
@@ -16,6 +16,7 @@ OBJS = \
 	conv.o \
 	encnames.o \
 	mbutils.o \
+	stringinfo_mb.o \
 	wchar.o \
 	wstrcmp.o \
 	wstrncmp.o
diff --git a/src/backend/utils/mb/stringinfo_mb.c b/src/backend/utils/mb/stringinfo_mb.c
new file mode 100644
index 0000000000..92771431e4
--- /dev/null
+++ b/src/backend/utils/mb/stringinfo_mb.c
@@ -0,0 +1,87 @@
+/*-------------------------------------------------------------------------
+ *
+ * stringinfo_mb.c
+ *
+ * multibyte-aware additional StringInfo facilites
+ *
+ * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *	  src/backend/utils/stringinfo_mb.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "lib/stringinfo.h"
+#include "mb/pg_wchar.h"
+#include "utils/memutils.h"
+
+
+/*
+ * appendStringInfoStringQuoted
+ *
+ * Append a null-terminated string to str, adding single quotes around it
+ * and doubling all single quotes.
+ */
+void
+appendStringInfoStringQuoted(StringInfo str, const char *s, int maxlen)
+{
+	char	   *copy = NULL;
+	const char *chunk_search_start,
+			   *chunk_copy_start,
+			   *chunk_end;
+	bool		ellipsis;
+	int			slen;
+
+	Assert(str != NULL);
+
+	slen = strlen(s);
+	if (maxlen > 0 && maxlen < slen)
+	{
+		int		finallen = pg_mbcliplen(s, slen, maxlen);
+
+		copy = pnstrdup(s, finallen);
+		chunk_search_start = copy;
+		chunk_copy_start = copy;
+
+		ellipsis = true;
+	}
+	else
+	{
+		chunk_search_start = s;
+		chunk_copy_start = s;
+
+		ellipsis = false;
+	}
+
+	appendStringInfoCharMacro(str, '\'');
+
+	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
+	{
+		/* copy including the found delimiting ' */
+		appendBinaryStringInfoNT(str,
+								 chunk_copy_start,
+								 chunk_end - chunk_copy_start + 1);
+
+		/* in order to double it, include this ' into the next chunk as well */
+		chunk_copy_start = chunk_end;
+		chunk_search_start = chunk_end + 1;
+	}
+
+	/* copy the last chunk and terminate */
+	if (ellipsis)
+		appendStringInfo(str, "%s...'", chunk_copy_start);
+	else
+	{
+		int		len = strlen(chunk_copy_start);
+
+		/* ensure sufficient space for terminators */
+		appendBinaryStringInfoNT(str, chunk_copy_start, len);
+		appendStringInfoCharMacro(str, '\'');
+	}
+
+	if (copy)
+		pfree(copy);
+}
diff --git a/src/common/stringinfo.c b/src/common/stringinfo.c
index a50e587da9..90970b54b7 100644
--- a/src/common/stringinfo.c
+++ b/src/common/stringinfo.c
@@ -30,6 +30,7 @@
 #endif
 
 #include "lib/stringinfo.h"
+#include "mb/pg_wchar.h"
 
 
 /*
diff --git a/src/include/lib/stringinfo.h b/src/include/lib/stringinfo.h
index e27942728e..aadd00b2fb 100644
--- a/src/include/lib/stringinfo.h
+++ b/src/include/lib/stringinfo.h
@@ -158,4 +158,18 @@ extern void appendBinaryStringInfoNT(StringInfo str,
  */
 extern void enlargeStringInfo(StringInfo str, int needed);
 
+/* In stringinfo_mb.c */
+#ifndef FRONTEND
+/*------------------------
+ * appendStringInfoStringQuoted
+ * Append up to maxlen characters from s (which is in the given encoding) to
+ * str, or the whole input string if maxlen <= 0, adding single quotes around
+ * it and doubling all single quotes.  Add an ellipsis if the copy is
+ * incomplete.
+ */
+extern void appendStringInfoStringQuoted(StringInfo str,
+										 const char *s, int maxlen);
+#endif
+
+
 #endif							/* STRINGINFO_H */
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 4f0de7a811..c3ae409f39 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -8611,19 +8611,11 @@ format_expr_params(PLpgSQL_execstate *estate,
 		if (paramisnull)
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, paramdatum, paramtypeid);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 paramdatum,
+																 paramtypeid),
+										 0);
 
 		paramno++;
 	}
@@ -8661,19 +8653,11 @@ format_preparedparamsdata(PLpgSQL_execstate *estate,
 		if (ppd->nulls[paramno] == 'n')
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, ppd->values[paramno], ppd->types[paramno]);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 ppd->values[paramno],
+																 ppd->types[paramno]),
+										 0);
 	}
 
 	MemoryContextSwitchTo(oldcontext);
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index e85b29455e..cd2c79f4d5 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -2656,6 +2656,20 @@ create or replace function stricttest() returns void as $$
 declare
 x record;
 p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+select stricttest();
+ERROR:  query returned no rows
+DETAIL:  parameters: p1 = '2', p3 = '''Valame Dios!'' dijo Sancho; ''no le dije yo a vuestra merced que mirase bien lo que hacia?'''
+CONTEXT:  PL/pgSQL function stricttest() line 8 at SQL statement
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
 p3 text := 'foo';
 begin
   -- too many rows
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index 70deadfbea..d841d8c0f9 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2280,6 +2280,19 @@ end$$ language plpgsql;
 
 select stricttest();
 
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+
+select stricttest();
+
 create or replace function stricttest() returns void as $$
 declare
 x record;
-- 
2.20.1

From 62277fcd3f63ae68495300c98f77c7e4b4713614 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Tue, 3 Dec 2019 10:08:35 -0300
Subject: [PATCH v20] Add backend-only appendStringInfoStringQuoted
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Simplifies some coding that prints parameters, as well as optimize to do
it per non-quote chunks instead of per byte.

This lives separetely from common/stringinfo.c so that frontend users of
that file need not pull in unnecessary multibyte-encoding support code.

Author: Álvaro Herrera and Alexey Bashtanov, after a suggestion from Andres Freund
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/20190920203905.xkv5udsd5dxfs6tr@alap3.anarazel.de
---
 src/backend/tcop/postgres.c           | 10 +--
 src/backend/utils/mb/Makefile         |  1 +
 src/backend/utils/mb/README           |  1 +
 src/backend/utils/mb/stringinfo_mb.c  | 92 +++++++++++++++++++++++++++
 src/pl/plpgsql/src/pl_exec.c          | 36 +++--------
 src/test/regress/expected/plpgsql.out | 14 ++++
 src/test/regress/sql/plpgsql.sql      | 13 ++++
 7 files changed, 132 insertions(+), 35 deletions(-)
 create mode 100644 src/backend/utils/mb/stringinfo_mb.c

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3b85e48333..3d3172e83d 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -2348,7 +2348,6 @@ errdetail_params(ParamListInfo params)
 			Oid			typoutput;
 			bool		typisvarlena;
 			char	   *pstring;
-			char	   *p;
 
 			appendStringInfo(&param_str, "%s$%d = ",
 							 paramno > 0 ? ", " : "",
@@ -2364,14 +2363,7 @@ errdetail_params(ParamListInfo params)
 
 			pstring = OidOutputFunctionCall(typoutput, prm->value);
 
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
+			appendStringInfoStringQuoted(&param_str, pstring, 0);
 
 			pfree(pstring);
 		}
diff --git a/src/backend/utils/mb/Makefile b/src/backend/utils/mb/Makefile
index 18dd758cfe..cd4a016449 100644
--- a/src/backend/utils/mb/Makefile
+++ b/src/backend/utils/mb/Makefile
@@ -16,6 +16,7 @@ OBJS = \
 	conv.o \
 	encnames.o \
 	mbutils.o \
+	stringinfo_mb.o \
 	wchar.o \
 	wstrcmp.o \
 	wstrncmp.o
diff --git a/src/backend/utils/mb/README b/src/backend/utils/mb/README
index c9bc6e6f8d..7495ca5db2 100644
--- a/src/backend/utils/mb/README
+++ b/src/backend/utils/mb/README
@@ -9,6 +9,7 @@ wchar.c:	mostly static functions and a public table for mb string and
 		multibyte conversion
 mbutils.c:	public functions for the backend only.
 		requires conv.c and wchar.c
+stringinfo_mb.c: public backend-only multibyte-aware stringinfo functions
 wstrcmp.c:	strcmp for mb
 wstrncmp.c:	strncmp for mb
 win866.c:	a tool to generate KOI8 <--> CP866 conversion table
diff --git a/src/backend/utils/mb/stringinfo_mb.c b/src/backend/utils/mb/stringinfo_mb.c
new file mode 100644
index 0000000000..baef1aa39a
--- /dev/null
+++ b/src/backend/utils/mb/stringinfo_mb.c
@@ -0,0 +1,92 @@
+/*-------------------------------------------------------------------------
+ *
+ * stringinfo_mb.c
+ *		Multibyte encoding-aware additional StringInfo facilites
+ *
+ * This is separate from common/stringinfo.c so that frontend users
+ * of that file need not pull in unnecessary multibyte-encoding support
+ * code.
+ *
+ *
+ * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  src/backend/utils/mb/stringinfo_mb.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "lib/stringinfo.h"
+#include "mb/pg_wchar.h"
+
+
+/*
+ * appendStringInfoStringQuoted
+ *
+ * Append up to maxlen characters from s to str, or the whole input string if
+ * maxlen <= 0, adding single quotes around it and doubling all single quotes.
+ * Add an ellipsis if the copy is incomplete.
+ */
+void
+appendStringInfoStringQuoted(StringInfo str, const char *s, int maxlen)
+{
+	char	   *copy = NULL;
+	const char *chunk_search_start,
+			   *chunk_copy_start,
+			   *chunk_end;
+	bool		ellipsis;
+	int			slen;
+
+	Assert(str != NULL);
+
+	slen = strlen(s);
+	if (maxlen > 0 && maxlen < slen)
+	{
+		int		finallen = pg_mbcliplen(s, slen, maxlen);
+
+		copy = pnstrdup(s, finallen);
+		chunk_search_start = copy;
+		chunk_copy_start = copy;
+
+		ellipsis = true;
+	}
+	else
+	{
+		chunk_search_start = s;
+		chunk_copy_start = s;
+
+		ellipsis = false;
+	}
+
+	appendStringInfoCharMacro(str, '\'');
+
+	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
+	{
+		/* copy including the found delimiting ' */
+		appendBinaryStringInfoNT(str,
+								 chunk_copy_start,
+								 chunk_end - chunk_copy_start + 1);
+
+		/* in order to double it, include this ' into the next chunk as well */
+		chunk_copy_start = chunk_end;
+		chunk_search_start = chunk_end + 1;
+	}
+
+	/* copy the last chunk and terminate */
+	if (ellipsis)
+		appendStringInfo(str, "%s...'", chunk_copy_start);
+	else
+	{
+		int		len = strlen(chunk_copy_start);
+
+		/* ensure sufficient space for terminators */
+		appendBinaryStringInfoNT(str, chunk_copy_start, len);
+		appendStringInfoCharMacro(str, '\'');
+	}
+
+	if (copy)
+		pfree(copy);
+}
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 4f0de7a811..c3ae409f39 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -8611,19 +8611,11 @@ format_expr_params(PLpgSQL_execstate *estate,
 		if (paramisnull)
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, paramdatum, paramtypeid);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 paramdatum,
+																 paramtypeid),
+										 0);
 
 		paramno++;
 	}
@@ -8661,19 +8653,11 @@ format_preparedparamsdata(PLpgSQL_execstate *estate,
 		if (ppd->nulls[paramno] == 'n')
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, ppd->values[paramno], ppd->types[paramno]);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 ppd->values[paramno],
+																 ppd->types[paramno]),
+										 0);
 	}
 
 	MemoryContextSwitchTo(oldcontext);
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index e85b29455e..cd2c79f4d5 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -2656,6 +2656,20 @@ create or replace function stricttest() returns void as $$
 declare
 x record;
 p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+select stricttest();
+ERROR:  query returned no rows
+DETAIL:  parameters: p1 = '2', p3 = '''Valame Dios!'' dijo Sancho; ''no le dije yo a vuestra merced que mirase bien lo que hacia?'''
+CONTEXT:  PL/pgSQL function stricttest() line 8 at SQL statement
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
 p3 text := 'foo';
 begin
   -- too many rows
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index 70deadfbea..d841d8c0f9 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2280,6 +2280,19 @@ end$$ language plpgsql;
 
 select stricttest();
 
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+
+select stricttest();
+
 create or replace function stricttest() returns void as $$
 declare
 x record;
-- 
2.20.1

From bd8df7f46556eb8a5de5e64f04b29f4d7a174d0e Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Tue, 10 Dec 2019 14:40:56 -0300
Subject: [PATCH v21] Add backend-only appendStringInfoStringQuoted
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This provides a mechanism to emit literal values in informative
messages, such as query parameters.  The new code is more complex than
what it replaces, primarily because it wants to be more efficient.
It also has the (currently unused) additional optional capability of
specifying a maximum size to print.

This lives separetely from common/stringinfo.c so that frontend users of
that file need not pull in unnecessary multibyte-encoding support code.

Author: Álvaro Herrera and Alexey Bashtanov, after a suggestion from Andres Freund
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/20190920203905.xkv5udsd5dxfs6tr@alap3.anarazel.de
---
 src/backend/tcop/postgres.c           | 11 +---
 src/backend/utils/mb/Makefile         |  1 +
 src/backend/utils/mb/README           |  1 +
 src/backend/utils/mb/stringinfo_mb.c  | 92 +++++++++++++++++++++++++++
 src/include/mb/stringinfo_mb.h        | 24 +++++++
 src/pl/plpgsql/src/pl_exec.c          | 37 ++++-------
 src/test/regress/expected/plpgsql.out | 14 ++++
 src/test/regress/sql/plpgsql.sql      | 13 ++++
 8 files changed, 158 insertions(+), 35 deletions(-)
 create mode 100644 src/backend/utils/mb/stringinfo_mb.c
 create mode 100644 src/include/mb/stringinfo_mb.h

diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 3b85e48333..512209a38c 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -48,6 +48,7 @@
 #include "libpq/pqformat.h"
 #include "libpq/pqsignal.h"
 #include "mb/pg_wchar.h"
+#include "mb/stringinfo_mb.h"
 #include "miscadmin.h"
 #include "nodes/print.h"
 #include "optimizer/optimizer.h"
@@ -2348,7 +2349,6 @@ errdetail_params(ParamListInfo params)
 			Oid			typoutput;
 			bool		typisvarlena;
 			char	   *pstring;
-			char	   *p;
 
 			appendStringInfo(&param_str, "%s$%d = ",
 							 paramno > 0 ? ", " : "",
@@ -2364,14 +2364,7 @@ errdetail_params(ParamListInfo params)
 
 			pstring = OidOutputFunctionCall(typoutput, prm->value);
 
-			appendStringInfoCharMacro(&param_str, '\'');
-			for (p = pstring; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&param_str, *p);
-				appendStringInfoCharMacro(&param_str, *p);
-			}
-			appendStringInfoCharMacro(&param_str, '\'');
+			appendStringInfoStringQuoted(&param_str, pstring, 0);
 
 			pfree(pstring);
 		}
diff --git a/src/backend/utils/mb/Makefile b/src/backend/utils/mb/Makefile
index 18dd758cfe..cd4a016449 100644
--- a/src/backend/utils/mb/Makefile
+++ b/src/backend/utils/mb/Makefile
@@ -16,6 +16,7 @@ OBJS = \
 	conv.o \
 	encnames.o \
 	mbutils.o \
+	stringinfo_mb.o \
 	wchar.o \
 	wstrcmp.o \
 	wstrncmp.o
diff --git a/src/backend/utils/mb/README b/src/backend/utils/mb/README
index c9bc6e6f8d..7495ca5db2 100644
--- a/src/backend/utils/mb/README
+++ b/src/backend/utils/mb/README
@@ -9,6 +9,7 @@ wchar.c:	mostly static functions and a public table for mb string and
 		multibyte conversion
 mbutils.c:	public functions for the backend only.
 		requires conv.c and wchar.c
+stringinfo_mb.c: public backend-only multibyte-aware stringinfo functions
 wstrcmp.c:	strcmp for mb
 wstrncmp.c:	strncmp for mb
 win866.c:	a tool to generate KOI8 <--> CP866 conversion table
diff --git a/src/backend/utils/mb/stringinfo_mb.c b/src/backend/utils/mb/stringinfo_mb.c
new file mode 100644
index 0000000000..e84b9ad36f
--- /dev/null
+++ b/src/backend/utils/mb/stringinfo_mb.c
@@ -0,0 +1,92 @@
+/*-------------------------------------------------------------------------
+ *
+ * stringinfo_mb.c
+ *		Multibyte encoding-aware additional StringInfo facilites
+ *
+ * This is separate from common/stringinfo.c so that frontend users
+ * of that file need not pull in unnecessary multibyte-encoding support
+ * code.
+ *
+ *
+ * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  src/backend/utils/mb/stringinfo_mb.c
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "mb/stringinfo_mb.h"
+#include "mb/pg_wchar.h"
+
+
+/*
+ * appendStringInfoStringQuoted
+ *
+ * Append up to maxlen characters from s to str, or the whole input string if
+ * maxlen <= 0, adding single quotes around it and doubling all single quotes.
+ * Add an ellipsis if the copy is incomplete.
+ */
+void
+appendStringInfoStringQuoted(StringInfo str, const char *s, int maxlen)
+{
+	char	   *copy = NULL;
+	const char *chunk_search_start,
+			   *chunk_copy_start,
+			   *chunk_end;
+	bool		ellipsis;
+	int			slen;
+
+	Assert(str != NULL);
+
+	slen = strlen(s);
+	if (maxlen > 0 && maxlen < slen)
+	{
+		int		finallen = pg_mbcliplen(s, slen, maxlen);
+
+		copy = pnstrdup(s, finallen);
+		chunk_search_start = copy;
+		chunk_copy_start = copy;
+
+		ellipsis = true;
+	}
+	else
+	{
+		chunk_search_start = s;
+		chunk_copy_start = s;
+
+		ellipsis = false;
+	}
+
+	appendStringInfoCharMacro(str, '\'');
+
+	while ((chunk_end = strchr(chunk_search_start, '\'')) != NULL)
+	{
+		/* copy including the found delimiting ' */
+		appendBinaryStringInfoNT(str,
+								 chunk_copy_start,
+								 chunk_end - chunk_copy_start + 1);
+
+		/* in order to double it, include this ' into the next chunk as well */
+		chunk_copy_start = chunk_end;
+		chunk_search_start = chunk_end + 1;
+	}
+
+	/* copy the last chunk and terminate */
+	if (ellipsis)
+		appendStringInfo(str, "%s...'", chunk_copy_start);
+	else
+	{
+		int		len = strlen(chunk_copy_start);
+
+		/* ensure sufficient space for terminators */
+		appendBinaryStringInfoNT(str, chunk_copy_start, len);
+		appendStringInfoCharMacro(str, '\'');
+	}
+
+	if (copy)
+		pfree(copy);
+}
diff --git a/src/include/mb/stringinfo_mb.h b/src/include/mb/stringinfo_mb.h
new file mode 100644
index 0000000000..e90ba8bc51
--- /dev/null
+++ b/src/include/mb/stringinfo_mb.h
@@ -0,0 +1,24 @@
+/*-------------------------------------------------------------------------
+ *
+ * stringinfo_mb.h
+ *	  multibyte support for StringInfo
+ *
+ * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/mb/stringinfo_mb.h
+ *-------------------------------------------------------------------------
+ */
+#ifndef STRINGINFO_MB_H
+#define STRINGINFO_MB_H
+
+
+#include "lib/stringinfo.h"
+
+/*
+ * Multibyte-aware StringInfo support function.
+ */
+extern void appendStringInfoStringQuoted(StringInfo str,
+										 const char *s, int maxlen);
+
+#endif							/* STRINGINFO_MB_H */
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 4f0de7a811..2deb7c0b12 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -28,6 +28,7 @@
 #include "executor/spi.h"
 #include "executor/spi_priv.h"
 #include "funcapi.h"
+#include "mb/stringinfo_mb.h"
 #include "miscadmin.h"
 #include "nodes/nodeFuncs.h"
 #include "optimizer/optimizer.h"
@@ -8611,19 +8612,11 @@ format_expr_params(PLpgSQL_execstate *estate,
 		if (paramisnull)
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, paramdatum, paramtypeid);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 paramdatum,
+																 paramtypeid),
+										 0);
 
 		paramno++;
 	}
@@ -8661,19 +8654,11 @@ format_preparedparamsdata(PLpgSQL_execstate *estate,
 		if (ppd->nulls[paramno] == 'n')
 			appendStringInfoString(&paramstr, "NULL");
 		else
-		{
-			char	   *value = convert_value_to_string(estate, ppd->values[paramno], ppd->types[paramno]);
-			char	   *p;
-
-			appendStringInfoCharMacro(&paramstr, '\'');
-			for (p = value; *p; p++)
-			{
-				if (*p == '\'') /* double single quotes */
-					appendStringInfoCharMacro(&paramstr, *p);
-				appendStringInfoCharMacro(&paramstr, *p);
-			}
-			appendStringInfoCharMacro(&paramstr, '\'');
-		}
+			appendStringInfoStringQuoted(&paramstr,
+										 convert_value_to_string(estate,
+																 ppd->values[paramno],
+																 ppd->types[paramno]),
+										 0);
 	}
 
 	MemoryContextSwitchTo(oldcontext);
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index e85b29455e..cd2c79f4d5 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -2656,6 +2656,20 @@ create or replace function stricttest() returns void as $$
 declare
 x record;
 p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+select stricttest();
+ERROR:  query returned no rows
+DETAIL:  parameters: p1 = '2', p3 = '''Valame Dios!'' dijo Sancho; ''no le dije yo a vuestra merced que mirase bien lo que hacia?'''
+CONTEXT:  PL/pgSQL function stricttest() line 8 at SQL statement
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
 p3 text := 'foo';
 begin
   -- too many rows
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index 70deadfbea..d841d8c0f9 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -2280,6 +2280,19 @@ end$$ language plpgsql;
 
 select stricttest();
 
+create or replace function stricttest() returns void as $$
+declare
+x record;
+p1 int := 2;
+p3 text := $a$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$a$;
+begin
+  -- no rows
+  select * from foo where f1 = p1 and f1::text = p3 into strict x;
+  raise notice 'x.f1 = %, x.f2 = %', x.f1, x.f2;
+end$$ language plpgsql;
+
+select stricttest();
+
 create or replace function stricttest() returns void as $$
 declare
 x record;
-- 
2.20.1

From 45eca917877ea72122478fded75d5722a18d92aa Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Mon, 2 Dec 2019 16:02:48 -0300
Subject: [PATCH v21 2/2] Emit parameter values during query bind/execute
 errors

---
 doc/src/sgml/config.sgml                      |  23 ++++
 src/backend/nodes/params.c                    | 114 +++++++++++++++++
 src/backend/tcop/postgres.c                   | 118 +++++++++++-------
 src/backend/utils/misc/guc.c                  |  10 ++
 src/backend/utils/misc/postgresql.conf.sample |   1 +
 src/bin/pgbench/t/001_pgbench_with_server.pl  |  35 ++++++
 src/include/nodes/params.h                    |  10 ++
 src/include/utils/guc.h                       |   1 +
 8 files changed, 265 insertions(+), 47 deletions(-)

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 53ac14490a..5d1c90282f 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6595,6 +6595,29 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether bind parameters are logged when a statement is logged
+        as a result of <xref linkend="guc-log-min-error-statement"/>.
+        It adds some overhead, as postgres will compute and store textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged.
+        This setting has no effect on statements logged due to
+        <xref linkend="guc-log-min-duration-statement"/> or
+        <xref linkend="guc-log-statement"/> settings, as they are always logged
+        with parameters.
+        The default is <literal>off</literal>.
+        Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index cf4387e40f..c3320ee1c4 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -15,11 +15,16 @@
 
 #include "postgres.h"
 
+#include "access/xact.h"
+#include "lib/stringinfo.h"
+#include "mb/stringinfo_mb.h"
 #include "nodes/bitmapset.h"
 #include "nodes/params.h"
 #include "storage/shmem.h"
 #include "utils/datum.h"
 #include "utils/lsyscache.h"
+#include "utils/memutils.h"
+#include "utils/portal.h"
 
 
 /*
@@ -44,6 +49,7 @@ makeParamList(int numParams)
 	retval->paramCompileArg = NULL;
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
+	retval->paramValuesStr = NULL;
 	retval->numParams = numParams;
 
 	return retval;
@@ -58,6 +64,8 @@ makeParamList(int numParams)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * paramValuesStr is not copied, either.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -158,6 +166,8 @@ EstimateParamListSpace(ParamListInfo paramLI)
  * RestoreParamList can be used to recreate a ParamListInfo based on the
  * serialized representation; this will be a static, self-contained copy
  * just as copyParamList would create.
+ *
+ * paramValuesStr is not included.
  */
 void
 SerializeParamList(ParamListInfo paramLI, char **start_address)
@@ -251,3 +261,107 @@ RestoreParamList(char **start_address)
 
 	return paramLI;
 }
+
+/*
+ * BuildParamLogString
+ *		Prepare for reporting parameter values.
+ *
+ * Create a string to represent parameters list for logging and save it to
+ * params->paramValuesStr. If caller already knows textual representations for
+ * some parameters, it can pass an array of exactly params->numParams values
+ * as knownTextValues, which can contain NULLs for the individual values not
+ * known.  NULL can be given if no parameters are known.
+ *
+ * If maxlen is not zero, that's the maximum number of characters of the
+ * input string printed; an ellipsis is added if more characters exist.
+ * (Added quotes are not considered.)
+ *
+ * This should only be called if log_parameters_on_error is set, or caller
+ * wants to report the query parameters for other reasons.
+ */
+void
+BuildParamLogString(ParamListInfo params, char **knownTextValues, int maxlen)
+{
+	MemoryContext tmpCxt,
+				oldCxt;
+	StringInfoData buf;
+
+	/*
+	 * Nothing to do if it's is already set; also, no work if the param fetch
+	 * hook is in use.  (Mostly because it's unimplemented ... but that's
+	 * because it doesn't seem a case worth pursuing.)  Also, avoid calling
+	 * user-defined I/O functions when in an aborted transaction.  It might
+	 * be possible to improve on this when some knownTextValues exist.
+	 */
+	if (params->paramValuesStr != NULL ||
+		params->paramFetch != NULL ||
+		IsAbortedTransactionBlockState())
+		return;
+
+	/* Initialize the output stringinfo, in caller's memory context */
+	initStringInfo(&buf);
+
+	/* Use a temporary context to call output functions, just in case */
+	tmpCxt = AllocSetContextCreate(CurrentMemoryContext,
+								   "BuildParamLogString",
+								   ALLOCSET_DEFAULT_SIZES);
+	oldCxt = MemoryContextSwitchTo(tmpCxt);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *param = &params->params[paramno];
+
+		appendStringInfo(&buf,
+						 "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (param->isnull || !OidIsValid(param->ptype))
+			appendStringInfoString(&buf, "NULL");
+		else
+		{
+			if (knownTextValues != NULL && knownTextValues[paramno] != NULL)
+				appendStringInfoStringQuoted(&buf, knownTextValues[paramno],
+											 maxlen);
+			else
+			{
+				Oid			typoutput;
+				bool		typisvarlena;
+				char	   *pstring;
+
+				getTypeOutputInfo(param->ptype, &typoutput, &typisvarlena);
+				pstring = OidOutputFunctionCall(typoutput, param->value);
+				appendStringInfoStringQuoted(&buf, pstring, maxlen);
+			}
+		}
+	}
+
+	params->paramValuesStr = buf.data;
+
+	MemoryContextSwitchTo(oldCxt);
+	MemoryContextDelete(tmpCxt);
+}
+
+/*
+ * ParamsErrorCallback - callback for printing parameters in error context
+ *
+ * Note that this is a no-op unless BuildParamLogString has been called
+ * beforehand.
+ */
+void
+ParamsErrorCallback(void *arg)
+{
+	ParamsErrorCbData *data = (ParamsErrorCbData *) arg;
+
+	if (data == NULL ||
+		data->params == NULL ||
+		data->params->paramValuesStr == NULL)
+		return;
+
+	if (data->portalName && data->portalName[0] != '\0')
+		errcontext("extended query \"%s\" with parameters: %s",
+				   data->portalName, data->params->paramValuesStr);
+	else
+		errcontext("extended query with parameters: %s",
+				   data->params->paramValuesStr);
+}
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 512209a38c..5eef1ae41c 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -1614,6 +1614,8 @@ exec_bind_message(StringInfo input_message)
 	bool		save_log_statement_stats = log_statement_stats;
 	bool		snapshot_set = false;
 	char		msec_str[32];
+	ParamsErrorCbData params_data;
+	ErrorContextCallback params_errcxt;
 
 	/* Get the fixed part of the message */
 	portal_name = pq_getmsgstring(input_message);
@@ -1753,6 +1755,8 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		char	  **knownTextValues = NULL;	/* allocate on first use */
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1820,9 +1824,32 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				/*
+				 * Free result of encoding conversion, if any, and save a copy
+				 * for later when logging parameters.
+				 */
+				if (pstring)
+				{
+					if (log_parameters_on_error)
+					{
+						MemoryContext	oldcxt;
+
+						oldcxt = MemoryContextSwitchTo(MessageContext);
+						if (knownTextValues == NULL)
+							knownTextValues =
+								palloc0(numParams * sizeof(char *));
+						/*
+						 * Note: must copy at least two more full characters
+						 * than BuildParamLogString wants to see; otherwise it
+						 * might fail to include the ellipsis.
+						 */
+						knownTextValues[paramno] =
+							pnstrdup(pstring, 64 + 2 * MAX_MULTIBYTE_CHAR_LEN);
+						MemoryContextSwitchTo(oldcxt);
+					}
+					if (pstring != pbuf.data)
+						pfree(pstring);
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1872,6 +1899,14 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/*
+		 * Prepare for printing parameters, if configured to do so.  (This is
+		 * saved in the portal, so that they'll appear when the query is
+		 * executed later.)
+		 */
+		if (log_parameters_on_error)
+			BuildParamLogString(params, knownTextValues, 64);
 	}
 	else
 		params = NULL;
@@ -1879,6 +1914,14 @@ exec_bind_message(StringInfo input_message)
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
+	/* Set the error callback so that parameters are logged, as needed  */
+	params_errcxt.previous = error_context_stack;
+	params_errcxt.callback = ParamsErrorCallback;
+	params_data.portalName = portal->name;
+	params_data.params = params;
+	params_errcxt.arg = (void *) &params_data;
+	error_context_stack = &params_errcxt;
+
 	/* Get the result format codes */
 	numRFormats = pq_getmsgint(input_message, 2);
 	if (numRFormats > 0)
@@ -1924,6 +1967,12 @@ exec_bind_message(StringInfo input_message)
 	 */
 	PortalSetResultFormat(portal, numRFormats, rformats);
 
+	/*
+	 * Done binding; remove the parameters error callback.  Entries emitted
+	 * later determine independently whether to log the parameters or not.
+	 */
+	error_context_stack = error_context_stack->previous;
+
 	/*
 	 * Send BindComplete.
 	 */
@@ -1980,6 +2029,8 @@ exec_execute_message(const char *portal_name, long max_rows)
 	bool		execute_is_fetch;
 	bool		was_logged = false;
 	char		msec_str[32];
+	ParamsErrorCbData params_data;
+	ErrorContextCallback params_errcxt;
 
 	/* Adjust destination to tell printtup.c what to do */
 	dest = whereToSendOutput;
@@ -2104,8 +2155,16 @@ exec_execute_message(const char *portal_name, long max_rows)
 	CHECK_FOR_INTERRUPTS();
 
 	/*
-	 * Okay to run the portal.
+	 * Okay to run the portal.  Set the error callback so that parameters are
+	 * logged.  The parameters must have been saved during the bind phase.
 	 */
+	params_errcxt.previous = error_context_stack;
+	params_errcxt.callback = ParamsErrorCallback;
+	params_data.portalName = portal->name;
+	params_data.params = portalParams;
+	params_errcxt.arg = (void *) &params_data;
+	error_context_stack = &params_errcxt;
+
 	if (max_rows <= 0)
 		max_rows = FETCH_ALL;
 
@@ -2119,6 +2178,9 @@ exec_execute_message(const char *portal_name, long max_rows)
 
 	receiver->rDestroy(receiver);
 
+	/* Done executing; remove the params error callback */
+	error_context_stack = error_context_stack->previous;
+
 	if (completed)
 	{
 		if (is_xact_command)
@@ -2329,51 +2391,13 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
+	if (params && params->numParams > 0)
 	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
+		BuildParamLogString(params, NULL, 0);
 
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoStringQuoted(&param_str, pstring, 0);
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
-
-		pfree(param_str.data);
-
-		MemoryContextSwitchTo(oldcontext);
+		if (params->paramValuesStr &&
+			params->paramValuesStr[0] != '\0')
+			errdetail("parameters: %s", params->paramValuesStr);
 	}
 
 	return 0;
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index ba74bf9f7d..8d951ce404 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -486,6 +486,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1300,6 +1301,15 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
+	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
 	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 9541879c1f..087190ce63 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -544,6 +544,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/bin/pgbench/t/001_pgbench_with_server.pl b/src/bin/pgbench/t/001_pgbench_with_server.pl
index 1845869016..021d7a1826 100644
--- a/src/bin/pgbench/t/001_pgbench_with_server.pl
+++ b/src/bin/pgbench/t/001_pgbench_with_server.pl
@@ -270,6 +270,41 @@ COMMIT;
 }
 	});
 
+# Verify server logging of parameters
+$node->append_conf('postgresql.conf', "log_parameters_on_error = true");
+$node->reload;
+pgbench(
+		'-n -t1 -c1 -M prepared',
+		2,
+		[],
+		[
+		qr{ERROR:  division by zero},
+		qr{CONTEXT:  extended query with parameters: \$1 = '1', \$2 = NULL}
+		],
+		'server parameter logging',
+		{
+			'001_param_1' => q{select '1' as one \gset
+SELECT 1 / (random() / 2)::int, :one::int, :two::int;
+}
+	});
+
+pgbench(
+		'-n -t1 -c1 -M prepared',
+		2,
+		[],
+		[
+		qr{ERROR:  invalid input syntax for type json},
+		qr[CONTEXT:  JSON data, line 1: \{ invalid\.\.\.
+extended query with parameters: \$1 = '\{ invalid ', \$2 = '''Valame Dios!'' dijo Sancho; ''no le dije yo a vuestra merced que ...'$]m
+		],
+		'server parameter logging',
+		{
+			'001_param_2' => q[select '{ invalid ' as value \gset
+select $$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$$ as long \gset
+select column1::jsonb from (values (:value), (:long)) as q;
+]
+	});
+
 # test expressions
 # command 1..3 and 23 depend on random seed which is used to call srandom.
 pgbench(
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd9046619c..d7a7e1f191 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -115,6 +115,7 @@ typedef struct ParamListInfoData
 	void	   *paramCompileArg;
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
+	char	   *paramValuesStr;		/* params as a single string for errors */
 	int			numParams;		/* nominal/maximum # of Params represented */
 
 	/*
@@ -149,6 +150,12 @@ typedef struct ParamExecData
 	bool		isnull;
 } ParamExecData;
 
+/* type of argument for ParamsErrorCallback */
+typedef struct ParamsErrorCbData
+{
+	const char	 *portalName;
+	ParamListInfo params;
+} ParamsErrorCbData;
 
 /* Functions found in src/backend/nodes/params.c */
 extern ParamListInfo makeParamList(int numParams);
@@ -156,5 +163,8 @@ extern ParamListInfo copyParamList(ParamListInfo from);
 extern Size EstimateParamListSpace(ParamListInfo paramLI);
 extern void SerializeParamList(ParamListInfo paramLI, char **start_address);
 extern ParamListInfo RestoreParamList(char **start_address);
+extern void BuildParamLogString(ParamListInfo params, char **paramTextValues,
+								int valueLen);
+extern void ParamsErrorCallback(void *arg);
 
 #endif							/* PARAMS_H */
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 50098e63fe..41d5e1d14a 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
-- 
2.20.1

From 57546105624ac5184a356dc227f0820240e61b62 Mon Sep 17 00:00:00 2001
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Mon, 2 Dec 2019 16:02:48 -0300
Subject: [PATCH v22] Emit parameter values during query bind/execute errors
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This makes such log entries more useful, since the cause of the error
can be dependent on the parameter values.

Author: Alexey Bashtanov, Álvaro Herrera
Discussion: https://postgr.es/m/0146a67b-a22a-0519-9082-bc29756b93a2@imap.cc
Reviewed-by: Peter Eisentraut, Andres Freund, Tom Lane
---
 doc/src/sgml/config.sgml                      |  23 ++++
 src/backend/nodes/params.c                    | 105 ++++++++++++++++
 src/backend/tcop/postgres.c                   | 119 +++++++++++-------
 src/backend/utils/misc/guc.c                  |  10 ++
 src/backend/utils/misc/postgresql.conf.sample |   1 +
 src/bin/pgbench/t/001_pgbench_with_server.pl  |  35 ++++++
 src/include/nodes/params.h                    |  10 ++
 src/include/utils/guc.h                       |   1 +
 8 files changed, 257 insertions(+), 47 deletions(-)

diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 53ac14490a..5d1c90282f 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -6595,6 +6595,29 @@ log_line_prefix = '%m [%p] %q%u@%d/%a '
       </listitem>
      </varlistentry>
 
+     <varlistentry id="guc-log-parameters-on-error" xreflabel="log_parameters_on_error">
+      <term><varname>log_parameters_on_error</varname> (<type>boolean</type>)
+      <indexterm>
+       <primary><varname>log_parameters_on_error</varname> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Controls whether bind parameters are logged when a statement is logged
+        as a result of <xref linkend="guc-log-min-error-statement"/>.
+        It adds some overhead, as postgres will compute and store textual
+        representations of parameter values in memory for all statements,
+        even if they eventually do not get logged.
+        This setting has no effect on statements logged due to
+        <xref linkend="guc-log-min-duration-statement"/> or
+        <xref linkend="guc-log-statement"/> settings, as they are always logged
+        with parameters.
+        The default is <literal>off</literal>.
+        Only superusers can change this setting.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="guc-log-statement" xreflabel="log_statement">
       <term><varname>log_statement</varname> (<type>enum</type>)
       <indexterm>
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index cf4387e40f..907da0e7cf 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -15,11 +15,14 @@
 
 #include "postgres.h"
 
+#include "access/xact.h"
+#include "mb/stringinfo_mb.h"
 #include "nodes/bitmapset.h"
 #include "nodes/params.h"
 #include "storage/shmem.h"
 #include "utils/datum.h"
 #include "utils/lsyscache.h"
+#include "utils/memutils.h"
 
 
 /*
@@ -44,6 +47,7 @@ makeParamList(int numParams)
 	retval->paramCompileArg = NULL;
 	retval->parserSetup = NULL;
 	retval->parserSetupArg = NULL;
+	retval->paramValuesStr = NULL;
 	retval->numParams = numParams;
 
 	return retval;
@@ -58,6 +62,8 @@ makeParamList(int numParams)
  * set of parameter values.  If dynamic parameter hooks are present, we
  * intentionally do not copy them into the result.  Rather, we forcibly
  * instantiate all available parameter values and copy the datum values.
+ *
+ * paramValuesStr is not copied, either.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -158,6 +164,8 @@ EstimateParamListSpace(ParamListInfo paramLI)
  * RestoreParamList can be used to recreate a ParamListInfo based on the
  * serialized representation; this will be a static, self-contained copy
  * just as copyParamList would create.
+ *
+ * paramValuesStr is not included.
  */
 void
 SerializeParamList(ParamListInfo paramLI, char **start_address)
@@ -251,3 +259,100 @@ RestoreParamList(char **start_address)
 
 	return paramLI;
 }
+
+/*
+ * BuildParamLogString
+ *		Return a string that represent the parameter list, for logging.
+ *
+ * If caller already knows textual representations for some parameters, it can
+ * pass an array of exactly params->numParams values as knownTextValues, which
+ * can contain NULLs for the individual values not known.  NULL can be given if
+ * no parameters are known.
+ *
+ * If maxlen is not zero, that's the maximum number of characters of the
+ * input string printed; an ellipsis is added if more characters exist.
+ * (Added quotes are not considered.)
+ */
+char *
+BuildParamLogString(ParamListInfo params, char **knownTextValues, int maxlen)
+{
+	MemoryContext tmpCxt,
+				oldCxt;
+	StringInfoData buf;
+
+	/*
+	 * No work if the param fetch hook is in use.  Also, it's not possible to
+	 * do this in an aborted transaction.  (It might be possible to improve on
+	 * this last point when some knownTextValues exist, but it seems tricky.)
+	 */
+	if (params->paramFetch != NULL ||
+		IsAbortedTransactionBlockState())
+		return NULL;
+
+	/* Initialize the output stringinfo, in caller's memory context */
+	initStringInfo(&buf);
+
+	/* Use a temporary context to call output functions, just in case */
+	tmpCxt = AllocSetContextCreate(CurrentMemoryContext,
+								   "BuildParamLogString",
+								   ALLOCSET_DEFAULT_SIZES);
+	oldCxt = MemoryContextSwitchTo(tmpCxt);
+
+	for (int paramno = 0; paramno < params->numParams; paramno++)
+	{
+		ParamExternData *param = &params->params[paramno];
+
+		appendStringInfo(&buf,
+						 "%s$%d = ",
+						 paramno > 0 ? ", " : "",
+						 paramno + 1);
+
+		if (param->isnull || !OidIsValid(param->ptype))
+			appendStringInfoString(&buf, "NULL");
+		else
+		{
+			if (knownTextValues != NULL && knownTextValues[paramno] != NULL)
+				appendStringInfoStringQuoted(&buf, knownTextValues[paramno],
+											 maxlen);
+			else
+			{
+				Oid			typoutput;
+				bool		typisvarlena;
+				char	   *pstring;
+
+				getTypeOutputInfo(param->ptype, &typoutput, &typisvarlena);
+				pstring = OidOutputFunctionCall(typoutput, param->value);
+				appendStringInfoStringQuoted(&buf, pstring, maxlen);
+			}
+		}
+	}
+
+	MemoryContextSwitchTo(oldCxt);
+	MemoryContextDelete(tmpCxt);
+
+	return buf.data;
+}
+
+/*
+ * ParamsErrorCallback - callback for printing parameters in error context
+ *
+ * Note that this is a no-op unless BuildParamLogString has been called
+ * beforehand.
+ */
+void
+ParamsErrorCallback(void *arg)
+{
+	ParamsErrorCbData *data = (ParamsErrorCbData *) arg;
+
+	if (data == NULL ||
+		data->params == NULL ||
+		data->params->paramValuesStr == NULL)
+		return;
+
+	if (data->portalName && data->portalName[0] != '\0')
+		errcontext("extended query \"%s\" with parameters: %s",
+				   data->portalName, data->params->paramValuesStr);
+	else
+		errcontext("extended query with parameters: %s",
+				   data->params->paramValuesStr);
+}
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 512209a38c..0b7bc1fd03 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -1614,6 +1614,8 @@ exec_bind_message(StringInfo input_message)
 	bool		save_log_statement_stats = log_statement_stats;
 	bool		snapshot_set = false;
 	char		msec_str[32];
+	ParamsErrorCbData params_data;
+	ErrorContextCallback params_errcxt;
 
 	/* Get the fixed part of the message */
 	portal_name = pq_getmsgstring(input_message);
@@ -1753,6 +1755,8 @@ exec_bind_message(StringInfo input_message)
 	 */
 	if (numParams > 0)
 	{
+		char	  **knownTextValues = NULL;	/* allocate on first use */
+
 		params = makeParamList(numParams);
 
 		for (int paramno = 0; paramno < numParams; paramno++)
@@ -1820,9 +1824,32 @@ exec_bind_message(StringInfo input_message)
 
 				pval = OidInputFunctionCall(typinput, pstring, typioparam, -1);
 
-				/* Free result of encoding conversion, if any */
-				if (pstring && pstring != pbuf.data)
-					pfree(pstring);
+				/*
+				 * Free result of encoding conversion, if any, and save a copy
+				 * for later when logging parameters.
+				 */
+				if (pstring)
+				{
+					if (log_parameters_on_error)
+					{
+						MemoryContext	oldcxt;
+
+						oldcxt = MemoryContextSwitchTo(MessageContext);
+						if (knownTextValues == NULL)
+							knownTextValues =
+								palloc0(numParams * sizeof(char *));
+						/*
+						 * Note: must copy at least two more full characters
+						 * than BuildParamLogString wants to see; otherwise it
+						 * might fail to include the ellipsis.
+						 */
+						knownTextValues[paramno] =
+							pnstrdup(pstring, 64 + 2 * MAX_MULTIBYTE_CHAR_LEN);
+						MemoryContextSwitchTo(oldcxt);
+					}
+					if (pstring != pbuf.data)
+						pfree(pstring);
+				}
 			}
 			else if (pformat == 1)	/* binary mode */
 			{
@@ -1872,6 +1899,15 @@ exec_bind_message(StringInfo input_message)
 			params->params[paramno].pflags = PARAM_FLAG_CONST;
 			params->params[paramno].ptype = ptype;
 		}
+
+		/*
+		 * Once all parameters have been received, prepare for printing them in
+		 * errors, if configured to do so.  (This is saved in the portal, so
+		 * that they'll appear when the query is executed later.)
+		 */
+		if (log_parameters_on_error)
+			params->paramValuesStr =
+				BuildParamLogString(params, knownTextValues, 64);
 	}
 	else
 		params = NULL;
@@ -1879,6 +1915,14 @@ exec_bind_message(StringInfo input_message)
 	/* Done storing stuff in portal's context */
 	MemoryContextSwitchTo(oldContext);
 
+	/* Set the error callback so that parameters are logged, as needed  */
+	params_data.portalName = portal->name;
+	params_data.params = params;
+	params_errcxt.previous = error_context_stack;
+	params_errcxt.callback = ParamsErrorCallback;
+	params_errcxt.arg = (void *) &params_data;
+	error_context_stack = &params_errcxt;
+
 	/* Get the result format codes */
 	numRFormats = pq_getmsgint(input_message, 2);
 	if (numRFormats > 0)
@@ -1924,6 +1968,12 @@ exec_bind_message(StringInfo input_message)
 	 */
 	PortalSetResultFormat(portal, numRFormats, rformats);
 
+	/*
+	 * Done binding; remove the parameters error callback.  Entries emitted
+	 * later determine independently whether to log the parameters or not.
+	 */
+	error_context_stack = error_context_stack->previous;
+
 	/*
 	 * Send BindComplete.
 	 */
@@ -1980,6 +2030,8 @@ exec_execute_message(const char *portal_name, long max_rows)
 	bool		execute_is_fetch;
 	bool		was_logged = false;
 	char		msec_str[32];
+	ParamsErrorCbData params_data;
+	ErrorContextCallback params_errcxt;
 
 	/* Adjust destination to tell printtup.c what to do */
 	dest = whereToSendOutput;
@@ -2104,8 +2156,16 @@ exec_execute_message(const char *portal_name, long max_rows)
 	CHECK_FOR_INTERRUPTS();
 
 	/*
-	 * Okay to run the portal.
+	 * Okay to run the portal.  Set the error callback so that parameters are
+	 * logged.  The parameters must have been saved during the bind phase.
 	 */
+	params_data.portalName = portal->name;
+	params_data.params = portalParams;
+	params_errcxt.previous = error_context_stack;
+	params_errcxt.callback = ParamsErrorCallback;
+	params_errcxt.arg = (void *) &params_data;
+	error_context_stack = &params_errcxt;
+
 	if (max_rows <= 0)
 		max_rows = FETCH_ALL;
 
@@ -2119,6 +2179,9 @@ exec_execute_message(const char *portal_name, long max_rows)
 
 	receiver->rDestroy(receiver);
 
+	/* Done executing; remove the params error callback */
+	error_context_stack = error_context_stack->previous;
+
 	if (completed)
 	{
 		if (is_xact_command)
@@ -2329,51 +2392,13 @@ errdetail_execute(List *raw_parsetree_list)
 static int
 errdetail_params(ParamListInfo params)
 {
-	/* We mustn't call user-defined I/O functions when in an aborted xact */
-	if (params && params->numParams > 0 && !IsAbortedTransactionBlockState())
+	if (params && params->numParams > 0)
 	{
-		StringInfoData param_str;
-		MemoryContext oldcontext;
+		char   *str;
 
-		/* This code doesn't support dynamic param lists */
-		Assert(params->paramFetch == NULL);
-
-		/* Make sure any trash is generated in MessageContext */
-		oldcontext = MemoryContextSwitchTo(MessageContext);
-
-		initStringInfo(&param_str);
-
-		for (int paramno = 0; paramno < params->numParams; paramno++)
-		{
-			ParamExternData *prm = &params->params[paramno];
-			Oid			typoutput;
-			bool		typisvarlena;
-			char	   *pstring;
-
-			appendStringInfo(&param_str, "%s$%d = ",
-							 paramno > 0 ? ", " : "",
-							 paramno + 1);
-
-			if (prm->isnull || !OidIsValid(prm->ptype))
-			{
-				appendStringInfoString(&param_str, "NULL");
-				continue;
-			}
-
-			getTypeOutputInfo(prm->ptype, &typoutput, &typisvarlena);
-
-			pstring = OidOutputFunctionCall(typoutput, prm->value);
-
-			appendStringInfoStringQuoted(&param_str, pstring, 0);
-
-			pfree(pstring);
-		}
-
-		errdetail("parameters: %s", param_str.data);
-
-		pfree(param_str.data);
-
-		MemoryContextSwitchTo(oldcontext);
+		str = BuildParamLogString(params, NULL, 0);
+		if (str && str[0] != '\0')
+			errdetail("parameters: %s", str);
 	}
 
 	return 0;
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index ba74bf9f7d..8d951ce404 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -486,6 +486,7 @@ extern const struct config_enum_entry dynamic_shared_memory_options[];
  * GUC option variables that are exported from this module
  */
 bool		log_duration = false;
+bool		log_parameters_on_error = false;
 bool		Debug_print_plan = false;
 bool		Debug_print_parse = false;
 bool		Debug_print_rewritten = false;
@@ -1300,6 +1301,15 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
+	{
+		{"log_parameters_on_error", PGC_SUSET, LOGGING_WHAT,
+			gettext_noop("Logs bind parameters of the logged statements where possible."),
+			NULL
+		},
+		&log_parameters_on_error,
+		false,
+		NULL, NULL, NULL
+	},
 	{
 		{"debug_print_parse", PGC_USERSET, LOGGING_WHAT,
 			gettext_noop("Logs each query's parse tree."),
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 9541879c1f..087190ce63 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -544,6 +544,7 @@
 					# e.g. '<%u%%%d> '
 #log_lock_waits = off			# log lock waits >= deadlock_timeout
 #log_statement = 'none'			# none, ddl, mod, all
+#log_parameters_on_error = off	# on error log statements with bind parameters
 #log_replication_commands = off
 #log_temp_files = -1			# log temporary files equal or larger
 					# than the specified size in kilobytes;
diff --git a/src/bin/pgbench/t/001_pgbench_with_server.pl b/src/bin/pgbench/t/001_pgbench_with_server.pl
index 1845869016..021d7a1826 100644
--- a/src/bin/pgbench/t/001_pgbench_with_server.pl
+++ b/src/bin/pgbench/t/001_pgbench_with_server.pl
@@ -270,6 +270,41 @@ COMMIT;
 }
 	});
 
+# Verify server logging of parameters
+$node->append_conf('postgresql.conf', "log_parameters_on_error = true");
+$node->reload;
+pgbench(
+		'-n -t1 -c1 -M prepared',
+		2,
+		[],
+		[
+		qr{ERROR:  division by zero},
+		qr{CONTEXT:  extended query with parameters: \$1 = '1', \$2 = NULL}
+		],
+		'server parameter logging',
+		{
+			'001_param_1' => q{select '1' as one \gset
+SELECT 1 / (random() / 2)::int, :one::int, :two::int;
+}
+	});
+
+pgbench(
+		'-n -t1 -c1 -M prepared',
+		2,
+		[],
+		[
+		qr{ERROR:  invalid input syntax for type json},
+		qr[CONTEXT:  JSON data, line 1: \{ invalid\.\.\.
+extended query with parameters: \$1 = '\{ invalid ', \$2 = '''Valame Dios!'' dijo Sancho; ''no le dije yo a vuestra merced que ...'$]m
+		],
+		'server parameter logging',
+		{
+			'001_param_2' => q[select '{ invalid ' as value \gset
+select $$'Valame Dios!' dijo Sancho; 'no le dije yo a vuestra merced que mirase bien lo que hacia?'$$ as long \gset
+select column1::jsonb from (values (:value), (:long)) as q;
+]
+	});
+
 # test expressions
 # command 1..3 and 23 depend on random seed which is used to call srandom.
 pgbench(
diff --git a/src/include/nodes/params.h b/src/include/nodes/params.h
index fd9046619c..c6310b892f 100644
--- a/src/include/nodes/params.h
+++ b/src/include/nodes/params.h
@@ -115,6 +115,7 @@ typedef struct ParamListInfoData
 	void	   *paramCompileArg;
 	ParserSetupHook parserSetup;	/* parser setup hook */
 	void	   *parserSetupArg;
+	char	   *paramValuesStr;		/* params as a single string for errors */
 	int			numParams;		/* nominal/maximum # of Params represented */
 
 	/*
@@ -149,6 +150,12 @@ typedef struct ParamExecData
 	bool		isnull;
 } ParamExecData;
 
+/* type of argument for ParamsErrorCallback */
+typedef struct ParamsErrorCbData
+{
+	const char	 *portalName;
+	ParamListInfo params;
+} ParamsErrorCbData;
 
 /* Functions found in src/backend/nodes/params.c */
 extern ParamListInfo makeParamList(int numParams);
@@ -156,5 +163,8 @@ extern ParamListInfo copyParamList(ParamListInfo from);
 extern Size EstimateParamListSpace(ParamListInfo paramLI);
 extern void SerializeParamList(ParamListInfo paramLI, char **start_address);
 extern ParamListInfo RestoreParamList(char **start_address);
+extern char *BuildParamLogString(ParamListInfo params, char **paramTextValues,
+								int valueLen);
+extern void ParamsErrorCallback(void *arg);
 
 #endif							/* PARAMS_H */
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 50098e63fe..41d5e1d14a 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -234,6 +234,7 @@ typedef enum
 
 /* GUC vars that are actually declared in guc.c, rather than elsewhere */
 extern bool log_duration;
+extern bool log_parameters_on_error;
 extern bool Debug_print_plan;
 extern bool Debug_print_parse;
 extern bool Debug_print_rewritten;
-- 
2.20.1