postgres_fdw hint messages

diff --git a/contrib/postgres_fdw/option.c b/contrib/postgres_fdw/option.c
index 95dde056eb..c0bcf489a7 100644
--- a/contrib/postgres_fdw/option.c
+++ b/contrib/postgres_fdw/option.c
@@ -222,36 +222,25 @@ InitPgFdwOptions(void)
 
 	/* non-libpq FDW-specific FDW options */
 	static const PgFdwOption non_libpq_options[] = {
-		{"schema_name", ForeignTableRelationId, false},
-		{"table_name", ForeignTableRelationId, false},
+		/* async_capable is available on both server and table */
+		{"async_capable", ForeignServerRelationId, false},
+		{"async_capable", ForeignTableRelationId, false},
+		/* batch_size is available on both server and table */
+		{"batch_size", ForeignServerRelationId, false},
+		{"batch_size", ForeignTableRelationId, false},
 		{"column_name", AttributeRelationId, false},
-		/* use_remote_estimate is available on both server and table */
-		{"use_remote_estimate", ForeignServerRelationId, false},
-		{"use_remote_estimate", ForeignTableRelationId, false},
-		/* cost factors */
-		{"fdw_startup_cost", ForeignServerRelationId, false},
-		{"fdw_tuple_cost", ForeignServerRelationId, false},
 		/* shippable extensions */
 		{"extensions", ForeignServerRelationId, false},
-		/* updatable is available on both server and table */
-		{"updatable", ForeignServerRelationId, false},
-		{"updatable", ForeignTableRelationId, false},
-		/* truncatable is available on both server and table */
-		{"truncatable", ForeignServerRelationId, false},
-		{"truncatable", ForeignTableRelationId, false},
+		{"fdw_startup_cost", ForeignServerRelationId, false},
+		{"fdw_tuple_cost", ForeignServerRelationId, false},
 		/* fetch_size is available on both server and table */
 		{"fetch_size", ForeignServerRelationId, false},
 		{"fetch_size", ForeignTableRelationId, false},
-		/* batch_size is available on both server and table */
-		{"batch_size", ForeignServerRelationId, false},
-		{"batch_size", ForeignTableRelationId, false},
-		/* async_capable is available on both server and table */
-		{"async_capable", ForeignServerRelationId, false},
-		{"async_capable", ForeignTableRelationId, false},
-		{"parallel_commit", ForeignServerRelationId, false},
+		/* cost factors */
 		{"keep_connections", ForeignServerRelationId, false},
+		{"parallel_commit", ForeignServerRelationId, false},
 		{"password_required", UserMappingRelationId, false},
-
+		{"schema_name", ForeignTableRelationId, false},
 		/*
 		 * sslcert and sslkey are in fact libpq options, but we repeat them
 		 * here to allow them to appear in both foreign server context (when
@@ -259,7 +248,16 @@ InitPgFdwOptions(void)
 		 */
 		{"sslcert", UserMappingRelationId, true},
 		{"sslkey", UserMappingRelationId, true},
-
+		{"table_name", ForeignTableRelationId, false},
+		/* truncatable is available on both server and table */
+		{"truncatable", ForeignServerRelationId, false},
+		{"truncatable", ForeignTableRelationId, false},
+		/* updatable is available on both server and table */
+		{"updatable", ForeignServerRelationId, false},
+		{"updatable", ForeignTableRelationId, false},
+		/* use_remote_estimate is available on both server and table */
+		{"use_remote_estimate", ForeignServerRelationId, false},
+		{"use_remote_estimate", ForeignTableRelationId, false},
 		{NULL, InvalidOid, false}
 	};
diff --git a/src/backend/foreign/foreign.c b/src/backend/foreign/foreign.c
index cf222fc3e9..fc4afb1e0b 100644
--- a/src/backend/foreign/foreign.c
+++ b/src/backend/foreign/foreign.c
@@ -560,19 +560,19 @@ struct ConnectionOption
  */
 static const struct ConnectionOption libpq_conninfo_options[] = {
 	{"authtype", ForeignServerRelationId},
-	{"service", ForeignServerRelationId},
-	{"user", UserMappingRelationId},
-	{"password", UserMappingRelationId},
 	{"connect_timeout", ForeignServerRelationId},
 	{"dbname", ForeignServerRelationId},
 	{"host", ForeignServerRelationId},
 	{"hostaddr", ForeignServerRelationId},
-	{"port", ForeignServerRelationId},
-	{"tty", ForeignServerRelationId},
+	{"gsslib", ForeignServerRelationId},
 	{"options", ForeignServerRelationId},
+	{"password", UserMappingRelationId},
+	{"port", ForeignServerRelationId},
 	{"requiressl", ForeignServerRelationId},
+	{"service", ForeignServerRelationId},
 	{"sslmode", ForeignServerRelationId},
-	{"gsslib", ForeignServerRelationId},
+	{"tty", ForeignServerRelationId},
+	{"user", UserMappingRelationId},
 	{NULL, InvalidOid}
 };
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 8cefef20d1..f5d05f13f4 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -186,25 +186,18 @@ typedef struct _internalPQconninfoOption
 } internalPQconninfoOption;
 
 static const internalPQconninfoOption PQconninfoOptions[] = {
-	{"service", "PGSERVICE", NULL, NULL,
-	"Database-Service", "", 20, -1},
-
-	{"user", "PGUSER", NULL, NULL,
-		"Database-User", "", 20,
-	offsetof(struct pg_conn, pguser)},
-
-	{"password", "PGPASSWORD", NULL, NULL,
-		"Database-Password", "*", 20,
-	offsetof(struct pg_conn, pgpass)},
-
-	{"passfile", "PGPASSFILE", NULL, NULL,
-		"Database-Password-File", "", 64,
-	offsetof(struct pg_conn, pgpassfile)},
+	{"application_name", "PGAPPNAME", NULL, NULL,
+		"Application-Name", "", 64,
+	offsetof(struct pg_conn, appname)},
 
 	{"channel_binding", "PGCHANNELBINDING", DefaultChannelBinding, NULL,
 		"Channel-Binding", "", 8,	/* sizeof("require") == 8 */
 	offsetof(struct pg_conn, channel_binding)},
 
+	{"client_encoding", "PGCLIENTENCODING", NULL, NULL,
+		"Client-Encoding", "", 10,
+	offsetof(struct pg_conn, client_encoding_initial)},
+
 	{"connect_timeout", "PGCONNECT_TIMEOUT", NULL, NULL,
 		"Connect-timeout", "", 10,	/* strlen(INT32_MAX) == 10 */
 	offsetof(struct pg_conn, connect_timeout)},
@@ -213,6 +206,10 @@ static const internalPQconninfoOption PQconninfoOptions[] = {
 		"Database-Name", "", 20,
 	offsetof(struct pg_conn, dbName)},
 
+	{"fallback_application_name", NULL, NULL, NULL,
+		"Fallback-Application-Name", "", 64,
+	offsetof(struct pg_conn, fbappname)},
+
 	{"host", "PGHOST", NULL, NULL,
 		"Database-Host", "", 40,
 	offsetof(struct pg_conn, pghost)},
@@ -221,30 +218,26 @@ static const internalPQconninfoOption PQconninfoOptions[] = {
 		"Database-Host-IP-Address", "", 45,
 	offsetof(struct pg_conn, pghostaddr)},
 
-	{"port", "PGPORT", DEF_PGPORT_STR, NULL,
-		"Database-Port", "", 6,
-	offsetof(struct pg_conn, pgport)},
-
-	{"client_encoding", "PGCLIENTENCODING", NULL, NULL,
-		"Client-Encoding", "", 10,
-	offsetof(struct pg_conn, client_encoding_initial)},
-
-	{"options", "PGOPTIONS", DefaultOption, NULL,
-		"Backend-Options", "", 40,
-	offsetof(struct pg_conn, pgoptions)},
-
-	{"application_name", "PGAPPNAME", NULL, NULL,
-		"Application-Name", "", 64,
-	offsetof(struct pg_conn, appname)},
+	/*
+	 * As with SSL, all GSS options are exposed even in builds that don't have
+	 * support.
+	 */
+	{"gssencmode", "PGGSSENCMODE", DefaultGSSMode, NULL,
+		"GSSENC-Mode", "", 8,	/* sizeof("disable") == 8 */
+	offsetof(struct pg_conn, gssencmode)},
 
-	{"fallback_application_name", NULL, NULL, NULL,
-		"Fallback-Application-Name", "", 64,
-	offsetof(struct pg_conn, fbappname)},
+	{"gsslib", "PGGSSLIB", NULL, NULL,
+		"GSS-library", "", 7,	/* sizeof("gssapi") == 7 */
+	offsetof(struct pg_conn, gsslib)},
 
 	{"keepalives", NULL, NULL, NULL,
 		"TCP-Keepalives", "", 1,	/* should be just '0' or '1' */
 	offsetof(struct pg_conn, keepalives)},
 
+	{"keepalives_count", NULL, NULL, NULL,
+		"TCP-Keepalives-Count", "", 10, /* strlen(INT32_MAX) == 10 */
+	offsetof(struct pg_conn, keepalives_count)},
+
 	{"keepalives_idle", NULL, NULL, NULL,
 		"TCP-Keepalives-Idle", "", 10,	/* strlen(INT32_MAX) == 10 */
 	offsetof(struct pg_conn, keepalives_idle)},
@@ -253,13 +246,37 @@ static const internalPQconninfoOption PQconninfoOptions[] = {
 		"TCP-Keepalives-Interval", "", 10,	/* strlen(INT32_MAX) == 10 */
 	offsetof(struct pg_conn, keepalives_interval)},
 
-	{"keepalives_count", NULL, NULL, NULL,
-		"TCP-Keepalives-Count", "", 10, /* strlen(INT32_MAX) == 10 */
-	offsetof(struct pg_conn, keepalives_count)},
+	/* Kerberos and GSSAPI authentication support specifying the service name */
+	{"krbsrvname", "PGKRBSRVNAME", PG_KRB_SRVNAM, NULL,
+		"Kerberos-service-name", "", 20,
+	offsetof(struct pg_conn, krbsrvname)},
 
-	{"tcp_user_timeout", NULL, NULL, NULL,
-		"TCP-User-Timeout", "", 10, /* strlen(INT32_MAX) == 10 */
-	offsetof(struct pg_conn, pgtcp_user_timeout)},
+	{"options", "PGOPTIONS", DefaultOption, NULL,
+		"Backend-Options", "", 40,
+	offsetof(struct pg_conn, pgoptions)},
+
+	{"password", "PGPASSWORD", NULL, NULL,
+		"Database-Password", "*", 20,
+	offsetof(struct pg_conn, pgpass)},
+
+	{"passfile", "PGPASSFILE", NULL, NULL,
+		"Database-Password-File", "", 64,
+	offsetof(struct pg_conn, pgpassfile)},
+
+	{"port", "PGPORT", DEF_PGPORT_STR, NULL,
+		"Database-Port", "", 6,
+	offsetof(struct pg_conn, pgport)},
+
+	{"replication", NULL, NULL, NULL,
+		"Replication", "D", 5,
+	offsetof(struct pg_conn, replication)},
+
+	{"requirepeer", "PGREQUIREPEER", NULL, NULL,
+		"Require-Peer", "", 10,
+	offsetof(struct pg_conn, requirepeer)},
+
+	{"service", "PGSERVICE", NULL, NULL,
+	"Database-Service", "", 20, -1},
 
 	/*
 	 * ssl options are allowed even without client SSL support because the
@@ -267,22 +284,30 @@ static const internalPQconninfoOption PQconninfoOptions[] = {
 	 * parameters have no effect on non-SSL connections, so there is no reason
 	 * to exclude them since none of them are mandatory.
 	 */
-	{"sslmode", "PGSSLMODE", DefaultSSLMode, NULL,
-		"SSL-Mode", "", 12,		/* sizeof("verify-full") == 12 */
-	offsetof(struct pg_conn, sslmode)},
+	{"sslcert", "PGSSLCERT", NULL, NULL,
+		"SSL-Client-Cert", "", 64,
+	offsetof(struct pg_conn, sslcert)},
 
 	{"sslcompression", "PGSSLCOMPRESSION", "0", NULL,
 		"SSL-Compression", "", 1,
 	offsetof(struct pg_conn, sslcompression)},
 
-	{"sslcert", "PGSSLCERT", NULL, NULL,
-		"SSL-Client-Cert", "", 64,
-	offsetof(struct pg_conn, sslcert)},
+	{"sslcrl", "PGSSLCRL", NULL, NULL,
+		"SSL-Revocation-List", "", 64,
+	offsetof(struct pg_conn, sslcrl)},
+
+	{"sslcrldir", "PGSSLCRLDIR", NULL, NULL,
+		"SSL-Revocation-List-Dir", "", 64,
+	offsetof(struct pg_conn, sslcrldir)},
 
 	{"sslkey", "PGSSLKEY", NULL, NULL,
 		"SSL-Client-Key", "", 64,
 	offsetof(struct pg_conn, sslkey)},
 
+	{"sslmode", "PGSSLMODE", DefaultSSLMode, NULL,
+		"SSL-Mode", "", 12,		/* sizeof("verify-full") == 12 */
+	offsetof(struct pg_conn, sslmode)},
+
 	{"sslpassword", NULL, NULL, NULL,
 		"SSL-Client-Key-Password", "*", 20,
 	offsetof(struct pg_conn, sslpassword)},
@@ -291,56 +316,31 @@ static const internalPQconninfoOption PQconninfoOptions[] = {
 		"SSL-Root-Certificate", "", 64,
 	offsetof(struct pg_conn, sslrootcert)},
 
-	{"sslcrl", "PGSSLCRL", NULL, NULL,
-		"SSL-Revocation-List", "", 64,
-	offsetof(struct pg_conn, sslcrl)},
-
-	{"sslcrldir", "PGSSLCRLDIR", NULL, NULL,
-		"SSL-Revocation-List-Dir", "", 64,
-	offsetof(struct pg_conn, sslcrldir)},
-
 	{"sslsni", "PGSSLSNI", "1", NULL,
 		"SSL-SNI", "", 1,
 	offsetof(struct pg_conn, sslsni)},
 
-	{"requirepeer", "PGREQUIREPEER", NULL, NULL,
-		"Require-Peer", "", 10,
-	offsetof(struct pg_conn, requirepeer)},
-
-	{"ssl_min_protocol_version", "PGSSLMINPROTOCOLVERSION", "TLSv1.2", NULL,
-		"SSL-Minimum-Protocol-Version", "", 8,	/* sizeof("TLSv1.x") == 8 */
-	offsetof(struct pg_conn, ssl_min_protocol_version)},
-
 	{"ssl_max_protocol_version", "PGSSLMAXPROTOCOLVERSION", NULL, NULL,
 		"SSL-Maximum-Protocol-Version", "", 8,	/* sizeof("TLSv1.x") == 8 */
 	offsetof(struct pg_conn, ssl_max_protocol_version)},
 
-	/*
-	 * As with SSL, all GSS options are exposed even in builds that don't have
-	 * support.
-	 */
-	{"gssencmode", "PGGSSENCMODE", DefaultGSSMode, NULL,
-		"GSSENC-Mode", "", 8,	/* sizeof("disable") == 8 */
-	offsetof(struct pg_conn, gssencmode)},
-
-	/* Kerberos and GSSAPI authentication support specifying the service name */
-	{"krbsrvname", "PGKRBSRVNAME", PG_KRB_SRVNAM, NULL,
-		"Kerberos-service-name", "", 20,
-	offsetof(struct pg_conn, krbsrvname)},
-
-	{"gsslib", "PGGSSLIB", NULL, NULL,
-		"GSS-library", "", 7,	/* sizeof("gssapi") == 7 */
-	offsetof(struct pg_conn, gsslib)},
-
-	{"replication", NULL, NULL, NULL,
-		"Replication", "D", 5,
-	offsetof(struct pg_conn, replication)},
+	{"ssl_min_protocol_version", "PGSSLMINPROTOCOLVERSION", "TLSv1.2", NULL,
+		"SSL-Minimum-Protocol-Version", "", 8,	/* sizeof("TLSv1.x") == 8 */
+	offsetof(struct pg_conn, ssl_min_protocol_version)},
 
 	{"target_session_attrs", "PGTARGETSESSIONATTRS",
 		DefaultTargetSessionAttrs, NULL,
 		"Target-Session-Attrs", "", 15, /* sizeof("prefer-standby") = 15 */
 	offsetof(struct pg_conn, target_session_attrs)},
 
+	{"tcp_user_timeout", NULL, NULL, NULL,
+		"TCP-User-Timeout", "", 10, /* strlen(INT32_MAX) == 10 */
+	offsetof(struct pg_conn, pgtcp_user_timeout)},
+
+	{"user", "PGUSER", NULL, NULL,
+		"Database-User", "", 20,
+	offsetof(struct pg_conn, pguser)},
+
 	/* Terminating entry --- MUST BE LAST */
 	{NULL, NULL, NULL, NULL,
 	NULL, NULL, 0}
diff --git a/src/test/regress/expected/foreign_data.out b/src/test/regress/expected/foreign_data.out
index 33505352cc..d5ffc4f16a 100644
--- a/src/test/regress/expected/foreign_data.out
+++ b/src/test/regress/expected/foreign_data.out
@@ -329,7 +329,7 @@ CREATE SERVER s6 VERSION '16.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbna
 CREATE SERVER s7 TYPE 'oracle' VERSION '17.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbname 'b');
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (foo '1'); -- ERROR
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
+HINT:  Valid options in this context are: authtype, connect_timeout, dbname, host, hostaddr, gsslib, options, port, requiressl, service, sslmode, tty
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (host 'localhost', dbname 's8db');
 \des+
                                                              List of foreign servers
@@ -440,7 +440,7 @@ ERROR:  permission denied for foreign-data wrapper foo
 RESET ROLE;
 ALTER SERVER s8 OPTIONS (foo '1');                          -- ERROR option validation
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
+HINT:  Valid options in this context are: authtype, connect_timeout, dbname, host, hostaddr, gsslib, options, port, requiressl, service, sslmode, tty
 ALTER SERVER s8 OPTIONS (connect_timeout '30', SET dbname 'db1', DROP host);
 SET ROLE regress_test_role;
 ALTER SERVER s1 OWNER TO regress_test_indirect;             -- ERROR
@@ -597,7 +597,7 @@ ERROR:  user mapping for "regress_foreign_data_user" already exists for server "
 CREATE USER MAPPING FOR public SERVER s4 OPTIONS ("this mapping" 'is public');
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (username 'test', password 'secret');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Valid options in this context are: password, user
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (user 'test', password 'secret');
 ALTER SERVER s5 OWNER TO regress_test_role;
 ALTER SERVER s6 OWNER TO regress_test_indirect;
@@ -636,7 +636,7 @@ ALTER USER MAPPING FOR public SERVER s5 OPTIONS (gotcha 'true');            -- E
 ERROR:  user mapping for "public" does not exist for server "s5"
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (username 'test');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Valid options in this context are: password, user
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (DROP user, SET password 'public');
 SET ROLE regress_test_role;
 ALTER USER MAPPING FOR current_user SERVER s5 OPTIONS (ADD modified '1');

diff --git a/contrib/postgres_fdw/option.c b/contrib/postgres_fdw/option.c
index 95dde056eb..eb76c07fa6 100644
--- a/contrib/postgres_fdw/option.c
+++ b/contrib/postgres_fdw/option.c
@@ -222,36 +222,25 @@ InitPgFdwOptions(void)
 
 	/* non-libpq FDW-specific FDW options */
 	static const PgFdwOption non_libpq_options[] = {
-		{"schema_name", ForeignTableRelationId, false},
-		{"table_name", ForeignTableRelationId, false},
+		/* async_capable is available on both server and table */
+		{"async_capable", ForeignServerRelationId, false},
+		{"async_capable", ForeignTableRelationId, false},
+		/* batch_size is available on both server and table */
+		{"batch_size", ForeignServerRelationId, false},
+		{"batch_size", ForeignTableRelationId, false},
 		{"column_name", AttributeRelationId, false},
-		/* use_remote_estimate is available on both server and table */
-		{"use_remote_estimate", ForeignServerRelationId, false},
-		{"use_remote_estimate", ForeignTableRelationId, false},
+		/* shippable extensions */
+		{"extensions", ForeignServerRelationId, false},
 		/* cost factors */
 		{"fdw_startup_cost", ForeignServerRelationId, false},
 		{"fdw_tuple_cost", ForeignServerRelationId, false},
-		/* shippable extensions */
-		{"extensions", ForeignServerRelationId, false},
-		/* updatable is available on both server and table */
-		{"updatable", ForeignServerRelationId, false},
-		{"updatable", ForeignTableRelationId, false},
-		/* truncatable is available on both server and table */
-		{"truncatable", ForeignServerRelationId, false},
-		{"truncatable", ForeignTableRelationId, false},
 		/* fetch_size is available on both server and table */
 		{"fetch_size", ForeignServerRelationId, false},
 		{"fetch_size", ForeignTableRelationId, false},
-		/* batch_size is available on both server and table */
-		{"batch_size", ForeignServerRelationId, false},
-		{"batch_size", ForeignTableRelationId, false},
-		/* async_capable is available on both server and table */
-		{"async_capable", ForeignServerRelationId, false},
-		{"async_capable", ForeignTableRelationId, false},
-		{"parallel_commit", ForeignServerRelationId, false},
 		{"keep_connections", ForeignServerRelationId, false},
+		{"parallel_commit", ForeignServerRelationId, false},
 		{"password_required", UserMappingRelationId, false},
-
+		{"schema_name", ForeignTableRelationId, false},
 		/*
 		 * sslcert and sslkey are in fact libpq options, but we repeat them
 		 * here to allow them to appear in both foreign server context (when
@@ -259,7 +248,16 @@ InitPgFdwOptions(void)
 		 */
 		{"sslcert", UserMappingRelationId, true},
 		{"sslkey", UserMappingRelationId, true},
-
+		{"table_name", ForeignTableRelationId, false},
+		/* truncatable is available on both server and table */
+		{"truncatable", ForeignServerRelationId, false},
+		{"truncatable", ForeignTableRelationId, false},
+		/* updatable is available on both server and table */
+		{"updatable", ForeignServerRelationId, false},
+		{"updatable", ForeignTableRelationId, false},
+		/* use_remote_estimate is available on both server and table */
+		{"use_remote_estimate", ForeignServerRelationId, false},
+		{"use_remote_estimate", ForeignTableRelationId, false},
 		{NULL, InvalidOid, false}
 	};
diff --git a/src/backend/foreign/foreign.c b/src/backend/foreign/foreign.c
index cf222fc3e9..fc4afb1e0b 100644
--- a/src/backend/foreign/foreign.c
+++ b/src/backend/foreign/foreign.c
@@ -560,19 +560,19 @@ struct ConnectionOption
  */
 static const struct ConnectionOption libpq_conninfo_options[] = {
 	{"authtype", ForeignServerRelationId},
-	{"service", ForeignServerRelationId},
-	{"user", UserMappingRelationId},
-	{"password", UserMappingRelationId},
 	{"connect_timeout", ForeignServerRelationId},
 	{"dbname", ForeignServerRelationId},
 	{"host", ForeignServerRelationId},
 	{"hostaddr", ForeignServerRelationId},
-	{"port", ForeignServerRelationId},
-	{"tty", ForeignServerRelationId},
+	{"gsslib", ForeignServerRelationId},
 	{"options", ForeignServerRelationId},
+	{"password", UserMappingRelationId},
+	{"port", ForeignServerRelationId},
 	{"requiressl", ForeignServerRelationId},
+	{"service", ForeignServerRelationId},
 	{"sslmode", ForeignServerRelationId},
-	{"gsslib", ForeignServerRelationId},
+	{"tty", ForeignServerRelationId},
+	{"user", UserMappingRelationId},
 	{NULL, InvalidOid}
 };
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 8cefef20d1..b6331618f8 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -186,25 +186,18 @@ typedef struct _internalPQconninfoOption
 } internalPQconninfoOption;
 
 static const internalPQconninfoOption PQconninfoOptions[] = {
-	{"service", "PGSERVICE", NULL, NULL,
-	"Database-Service", "", 20, -1},
-
-	{"user", "PGUSER", NULL, NULL,
-		"Database-User", "", 20,
-	offsetof(struct pg_conn, pguser)},
-
-	{"password", "PGPASSWORD", NULL, NULL,
-		"Database-Password", "*", 20,
-	offsetof(struct pg_conn, pgpass)},
-
-	{"passfile", "PGPASSFILE", NULL, NULL,
-		"Database-Password-File", "", 64,
-	offsetof(struct pg_conn, pgpassfile)},
+	{"application_name", "PGAPPNAME", NULL, NULL,
+		"Application-Name", "", 64,
+	offsetof(struct pg_conn, appname)},
 
 	{"channel_binding", "PGCHANNELBINDING", DefaultChannelBinding, NULL,
 		"Channel-Binding", "", 8,	/* sizeof("require") == 8 */
 	offsetof(struct pg_conn, channel_binding)},
 
+	{"client_encoding", "PGCLIENTENCODING", NULL, NULL,
+		"Client-Encoding", "", 10,
+	offsetof(struct pg_conn, client_encoding_initial)},
+
 	{"connect_timeout", "PGCONNECT_TIMEOUT", NULL, NULL,
 		"Connect-timeout", "", 10,	/* strlen(INT32_MAX) == 10 */
 	offsetof(struct pg_conn, connect_timeout)},
@@ -213,6 +206,10 @@ static const internalPQconninfoOption PQconninfoOptions[] = {
 		"Database-Name", "", 20,
 	offsetof(struct pg_conn, dbName)},
 
+	{"fallback_application_name", NULL, NULL, NULL,
+		"Fallback-Application-Name", "", 64,
+	offsetof(struct pg_conn, fbappname)},
+
 	{"host", "PGHOST", NULL, NULL,
 		"Database-Host", "", 40,
 	offsetof(struct pg_conn, pghost)},
@@ -221,30 +218,27 @@ static const internalPQconninfoOption PQconninfoOptions[] = {
 		"Database-Host-IP-Address", "", 45,
 	offsetof(struct pg_conn, pghostaddr)},
 
-	{"port", "PGPORT", DEF_PGPORT_STR, NULL,
-		"Database-Port", "", 6,
-	offsetof(struct pg_conn, pgport)},
-
-	{"client_encoding", "PGCLIENTENCODING", NULL, NULL,
-		"Client-Encoding", "", 10,
-	offsetof(struct pg_conn, client_encoding_initial)},
-
-	{"options", "PGOPTIONS", DefaultOption, NULL,
-		"Backend-Options", "", 40,
-	offsetof(struct pg_conn, pgoptions)},
-
-	{"application_name", "PGAPPNAME", NULL, NULL,
-		"Application-Name", "", 64,
-	offsetof(struct pg_conn, appname)},
+	/*
+	 * As with SSL, all GSS options are exposed even in builds that don't have
+	 * support.
+	 */
+	{"gssencmode", "PGGSSENCMODE", DefaultGSSMode, NULL,
+		"GSSENC-Mode", "", 8,	/* sizeof("disable") == 8 */
+	offsetof(struct pg_conn, gssencmode)},
 
-	{"fallback_application_name", NULL, NULL, NULL,
-		"Fallback-Application-Name", "", 64,
-	offsetof(struct pg_conn, fbappname)},
+	/* GSSAPI authentication support specifying the service name */
+	{"gsslib", "PGGSSLIB", NULL, NULL,
+		"GSS-library", "", 7,	/* sizeof("gssapi") == 7 */
+	offsetof(struct pg_conn, gsslib)},
 
 	{"keepalives", NULL, NULL, NULL,
 		"TCP-Keepalives", "", 1,	/* should be just '0' or '1' */
 	offsetof(struct pg_conn, keepalives)},
 
+	{"keepalives_count", NULL, NULL, NULL,
+		"TCP-Keepalives-Count", "", 10, /* strlen(INT32_MAX) == 10 */
+	offsetof(struct pg_conn, keepalives_count)},
+
 	{"keepalives_idle", NULL, NULL, NULL,
 		"TCP-Keepalives-Idle", "", 10,	/* strlen(INT32_MAX) == 10 */
 	offsetof(struct pg_conn, keepalives_idle)},
@@ -253,13 +247,37 @@ static const internalPQconninfoOption PQconninfoOptions[] = {
 		"TCP-Keepalives-Interval", "", 10,	/* strlen(INT32_MAX) == 10 */
 	offsetof(struct pg_conn, keepalives_interval)},
 
-	{"keepalives_count", NULL, NULL, NULL,
-		"TCP-Keepalives-Count", "", 10, /* strlen(INT32_MAX) == 10 */
-	offsetof(struct pg_conn, keepalives_count)},
+	/* Kerberos authentication support specifying the service name */
+	{"krbsrvname", "PGKRBSRVNAME", PG_KRB_SRVNAM, NULL,
+		"Kerberos-service-name", "", 20,
+	offsetof(struct pg_conn, krbsrvname)},
 
-	{"tcp_user_timeout", NULL, NULL, NULL,
-		"TCP-User-Timeout", "", 10, /* strlen(INT32_MAX) == 10 */
-	offsetof(struct pg_conn, pgtcp_user_timeout)},
+	{"options", "PGOPTIONS", DefaultOption, NULL,
+		"Backend-Options", "", 40,
+	offsetof(struct pg_conn, pgoptions)},
+
+	{"password", "PGPASSWORD", NULL, NULL,
+		"Database-Password", "*", 20,
+	offsetof(struct pg_conn, pgpass)},
+
+	{"passfile", "PGPASSFILE", NULL, NULL,
+		"Database-Password-File", "", 64,
+	offsetof(struct pg_conn, pgpassfile)},
+
+	{"port", "PGPORT", DEF_PGPORT_STR, NULL,
+		"Database-Port", "", 6,
+	offsetof(struct pg_conn, pgport)},
+
+	{"replication", NULL, NULL, NULL,
+		"Replication", "D", 5,
+	offsetof(struct pg_conn, replication)},
+
+	{"requirepeer", "PGREQUIREPEER", NULL, NULL,
+		"Require-Peer", "", 10,
+	offsetof(struct pg_conn, requirepeer)},
+
+	{"service", "PGSERVICE", NULL, NULL,
+	"Database-Service", "", 20, -1},
 
 	/*
 	 * ssl options are allowed even without client SSL support because the
@@ -267,22 +285,30 @@ static const internalPQconninfoOption PQconninfoOptions[] = {
 	 * parameters have no effect on non-SSL connections, so there is no reason
 	 * to exclude them since none of them are mandatory.
 	 */
-	{"sslmode", "PGSSLMODE", DefaultSSLMode, NULL,
-		"SSL-Mode", "", 12,		/* sizeof("verify-full") == 12 */
-	offsetof(struct pg_conn, sslmode)},
+	{"sslcert", "PGSSLCERT", NULL, NULL,
+		"SSL-Client-Cert", "", 64,
+	offsetof(struct pg_conn, sslcert)},
 
 	{"sslcompression", "PGSSLCOMPRESSION", "0", NULL,
 		"SSL-Compression", "", 1,
 	offsetof(struct pg_conn, sslcompression)},
 
-	{"sslcert", "PGSSLCERT", NULL, NULL,
-		"SSL-Client-Cert", "", 64,
-	offsetof(struct pg_conn, sslcert)},
+	{"sslcrl", "PGSSLCRL", NULL, NULL,
+		"SSL-Revocation-List", "", 64,
+	offsetof(struct pg_conn, sslcrl)},
+
+	{"sslcrldir", "PGSSLCRLDIR", NULL, NULL,
+		"SSL-Revocation-List-Dir", "", 64,
+	offsetof(struct pg_conn, sslcrldir)},
 
 	{"sslkey", "PGSSLKEY", NULL, NULL,
 		"SSL-Client-Key", "", 64,
 	offsetof(struct pg_conn, sslkey)},
 
+	{"sslmode", "PGSSLMODE", DefaultSSLMode, NULL,
+		"SSL-Mode", "", 12,		/* sizeof("verify-full") == 12 */
+	offsetof(struct pg_conn, sslmode)},
+
 	{"sslpassword", NULL, NULL, NULL,
 		"SSL-Client-Key-Password", "*", 20,
 	offsetof(struct pg_conn, sslpassword)},
@@ -291,56 +317,31 @@ static const internalPQconninfoOption PQconninfoOptions[] = {
 		"SSL-Root-Certificate", "", 64,
 	offsetof(struct pg_conn, sslrootcert)},
 
-	{"sslcrl", "PGSSLCRL", NULL, NULL,
-		"SSL-Revocation-List", "", 64,
-	offsetof(struct pg_conn, sslcrl)},
-
-	{"sslcrldir", "PGSSLCRLDIR", NULL, NULL,
-		"SSL-Revocation-List-Dir", "", 64,
-	offsetof(struct pg_conn, sslcrldir)},
-
 	{"sslsni", "PGSSLSNI", "1", NULL,
 		"SSL-SNI", "", 1,
 	offsetof(struct pg_conn, sslsni)},
 
-	{"requirepeer", "PGREQUIREPEER", NULL, NULL,
-		"Require-Peer", "", 10,
-	offsetof(struct pg_conn, requirepeer)},
-
-	{"ssl_min_protocol_version", "PGSSLMINPROTOCOLVERSION", "TLSv1.2", NULL,
-		"SSL-Minimum-Protocol-Version", "", 8,	/* sizeof("TLSv1.x") == 8 */
-	offsetof(struct pg_conn, ssl_min_protocol_version)},
-
 	{"ssl_max_protocol_version", "PGSSLMAXPROTOCOLVERSION", NULL, NULL,
 		"SSL-Maximum-Protocol-Version", "", 8,	/* sizeof("TLSv1.x") == 8 */
 	offsetof(struct pg_conn, ssl_max_protocol_version)},
 
-	/*
-	 * As with SSL, all GSS options are exposed even in builds that don't have
-	 * support.
-	 */
-	{"gssencmode", "PGGSSENCMODE", DefaultGSSMode, NULL,
-		"GSSENC-Mode", "", 8,	/* sizeof("disable") == 8 */
-	offsetof(struct pg_conn, gssencmode)},
-
-	/* Kerberos and GSSAPI authentication support specifying the service name */
-	{"krbsrvname", "PGKRBSRVNAME", PG_KRB_SRVNAM, NULL,
-		"Kerberos-service-name", "", 20,
-	offsetof(struct pg_conn, krbsrvname)},
-
-	{"gsslib", "PGGSSLIB", NULL, NULL,
-		"GSS-library", "", 7,	/* sizeof("gssapi") == 7 */
-	offsetof(struct pg_conn, gsslib)},
-
-	{"replication", NULL, NULL, NULL,
-		"Replication", "D", 5,
-	offsetof(struct pg_conn, replication)},
+	{"ssl_min_protocol_version", "PGSSLMINPROTOCOLVERSION", "TLSv1.2", NULL,
+		"SSL-Minimum-Protocol-Version", "", 8,	/* sizeof("TLSv1.x") == 8 */
+	offsetof(struct pg_conn, ssl_min_protocol_version)},
 
 	{"target_session_attrs", "PGTARGETSESSIONATTRS",
 		DefaultTargetSessionAttrs, NULL,
 		"Target-Session-Attrs", "", 15, /* sizeof("prefer-standby") = 15 */
 	offsetof(struct pg_conn, target_session_attrs)},
 
+	{"tcp_user_timeout", NULL, NULL, NULL,
+		"TCP-User-Timeout", "", 10, /* strlen(INT32_MAX) == 10 */
+	offsetof(struct pg_conn, pgtcp_user_timeout)},
+
+	{"user", "PGUSER", NULL, NULL,
+		"Database-User", "", 20,
+	offsetof(struct pg_conn, pguser)},
+
 	/* Terminating entry --- MUST BE LAST */
 	{NULL, NULL, NULL, NULL,
 	NULL, NULL, 0}
diff --git a/src/test/regress/expected/foreign_data.out b/src/test/regress/expected/foreign_data.out
index 33505352cc..d5ffc4f16a 100644
--- a/src/test/regress/expected/foreign_data.out
+++ b/src/test/regress/expected/foreign_data.out
@@ -329,7 +329,7 @@ CREATE SERVER s6 VERSION '16.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbna
 CREATE SERVER s7 TYPE 'oracle' VERSION '17.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbname 'b');
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (foo '1'); -- ERROR
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
+HINT:  Valid options in this context are: authtype, connect_timeout, dbname, host, hostaddr, gsslib, options, port, requiressl, service, sslmode, tty
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (host 'localhost', dbname 's8db');
 \des+
                                                              List of foreign servers
@@ -440,7 +440,7 @@ ERROR:  permission denied for foreign-data wrapper foo
 RESET ROLE;
 ALTER SERVER s8 OPTIONS (foo '1');                          -- ERROR option validation
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
+HINT:  Valid options in this context are: authtype, connect_timeout, dbname, host, hostaddr, gsslib, options, port, requiressl, service, sslmode, tty
 ALTER SERVER s8 OPTIONS (connect_timeout '30', SET dbname 'db1', DROP host);
 SET ROLE regress_test_role;
 ALTER SERVER s1 OWNER TO regress_test_indirect;             -- ERROR
@@ -597,7 +597,7 @@ ERROR:  user mapping for "regress_foreign_data_user" already exists for server "
 CREATE USER MAPPING FOR public SERVER s4 OPTIONS ("this mapping" 'is public');
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (username 'test', password 'secret');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Valid options in this context are: password, user
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (user 'test', password 'secret');
 ALTER SERVER s5 OWNER TO regress_test_role;
 ALTER SERVER s6 OWNER TO regress_test_indirect;
@@ -636,7 +636,7 @@ ALTER USER MAPPING FOR public SERVER s5 OPTIONS (gotcha 'true');            -- E
 ERROR:  user mapping for "public" does not exist for server "s5"
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (username 'test');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Valid options in this context are: password, user
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (DROP user, SET password 'public');
 SET ROLE regress_test_role;
 ALTER USER MAPPING FOR current_user SERVER s5 OPTIONS (ADD modified '1');

From c079cf33ad8033875a6e18b9cff06e47330007ac Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Thu, 25 Aug 2022 15:31:10 +0200
Subject: [PATCH v2 1/2] postgres_fdw: Remove useless DO block in test

---
 contrib/postgres_fdw/expected/postgres_fdw.out | 8 +-------
 contrib/postgres_fdw/sql/postgres_fdw.sql      | 6 +-----
 2 files changed, 2 insertions(+), 12 deletions(-)

diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 7bf35602b0..a42c9720c3 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -9621,15 +9621,9 @@ ERROR:  password is required
 DETAIL:  Non-superusers must provide a password in the user mapping.
 -- If we add a password to the connstr it'll fail, because we don't allow passwords
 -- in connstrs only in user mappings.
-DO $d$
-    BEGIN
-        EXECUTE $$ALTER SERVER loopback_nopw OPTIONS (ADD password 'dummypw')$$;
-    END;
-$d$;
+ALTER SERVER loopback_nopw OPTIONS (ADD password 'dummypw');
 ERROR:  invalid option "password"
 HINT:  Valid options in this context are: service, passfile, channel_binding, connect_timeout, dbname, host, hostaddr, port, options, application_name, keepalives, keepalives_idle, keepalives_interval, keepalives_count, tcp_user_timeout, sslmode, sslcompression, sslcert, sslkey, sslrootcert, sslcrl, sslcrldir, sslsni, requirepeer, ssl_min_protocol_version, ssl_max_protocol_version, gssencmode, krbsrvname, gsslib, target_session_attrs, use_remote_estimate, fdw_startup_cost, fdw_tuple_cost, extensions, updatable, truncatable, fetch_size, batch_size, async_capable, parallel_commit, keep_connections
-CONTEXT:  SQL statement "ALTER SERVER loopback_nopw OPTIONS (ADD password 'dummypw')"
-PL/pgSQL function inline_code_block line 3 at EXECUTE
 -- If we add a password for our user mapping instead, we should get a different
 -- error because the password wasn't actually *used* when we run with trust auth.
 --
diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql
index 42735ae78a..63581a457d 100644
--- a/contrib/postgres_fdw/sql/postgres_fdw.sql
+++ b/contrib/postgres_fdw/sql/postgres_fdw.sql
@@ -2886,11 +2886,7 @@ CREATE FOREIGN TABLE pg_temp.ft1_nopw (
 -- If we add a password to the connstr it'll fail, because we don't allow passwords
 -- in connstrs only in user mappings.
 
-DO $d$
-    BEGIN
-        EXECUTE $$ALTER SERVER loopback_nopw OPTIONS (ADD password 'dummypw')$$;
-    END;
-$d$;
+ALTER SERVER loopback_nopw OPTIONS (ADD password 'dummypw');
 
 -- If we add a password for our user mapping instead, we should get a different
 -- error because the password wasn't actually *used* when we run with trust auth.
-- 
2.37.1

From eef24034a75e674e7e4a929557906395eab7673f Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Tue, 30 Aug 2022 09:08:53 +0200
Subject: [PATCH v2 2/2] Remove hints from FDW's invalid option errors

The FDWs provided in tree all had code to list valid options in an
error message hint if an invalid option was given to a
forein-data-related command.  These lists have in some cases gotten
extremely bulky, and in general they don't really help the user
correct their command.  (They might help in case of typos, but not if
there is a semantic misunderstanding about how the foreign-data setup
should be configured.)  So per discussion, remove these hints.

Discussion: https://www.postgresql.org/message-id/flat/b1f9f399-3a1a-b554-283f-4ae7f34608e2%40enterprisedb.com
---
 contrib/dblink/dblink.c                       | 24 +------------------
 contrib/dblink/expected/dblink.out            |  2 --
 contrib/file_fdw/expected/file_fdw.out        |  8 -------
 contrib/file_fdw/file_fdw.c                   | 23 +-----------------
 .../postgres_fdw/expected/postgres_fdw.out    |  3 ---
 contrib/postgres_fdw/option.c                 | 23 +-----------------
 src/backend/foreign/foreign.c                 | 19 +--------------
 src/test/regress/expected/foreign_data.out    |  5 ----
 8 files changed, 4 insertions(+), 103 deletions(-)

diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
index e323fdd0e6..d50a4bf240 100644
--- a/contrib/dblink/dblink.c
+++ b/contrib/dblink/dblink.c
@@ -2005,31 +2005,9 @@ dblink_fdw_validator(PG_FUNCTION_ARGS)
 		DefElem    *def = (DefElem *) lfirst(cell);
 
 		if (!is_valid_dblink_option(options, def->defname, context))
-		{
-			/*
-			 * Unknown option, or invalid option for the context specified, so
-			 * complain about it.  Provide a hint with list of valid options
-			 * for the context.
-			 */
-			StringInfoData buf;
-			const PQconninfoOption *opt;
-
-			initStringInfo(&buf);
-			for (opt = options; opt->keyword; opt++)
-			{
-				if (is_valid_dblink_option(options, opt->keyword, context))
-					appendStringInfo(&buf, "%s%s",
-									 (buf.len > 0) ? ", " : "",
-									 opt->keyword);
-			}
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_OPTION_NAME_NOT_FOUND),
-					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
-		}
+					 errmsg("invalid option \"%s\"", def->defname)));
 	}
 
 	PG_RETURN_VOID();
diff --git a/contrib/dblink/expected/dblink.out b/contrib/dblink/expected/dblink.out
index c7bde6ad07..a6f41a746c 100644
--- a/contrib/dblink/expected/dblink.out
+++ b/contrib/dblink/expected/dblink.out
@@ -897,7 +897,6 @@ $d$;
 CREATE USER MAPPING FOR public SERVER fdtest
   OPTIONS (server 'localhost');  -- fail, can't specify server here
 ERROR:  invalid option "server"
-HINT:  Valid options in this context are: user, password, sslpassword
 CREATE USER MAPPING FOR public SERVER fdtest OPTIONS (user :'USER');
 GRANT USAGE ON FOREIGN SERVER fdtest TO regress_dblink_user;
 GRANT EXECUTE ON FUNCTION dblink_connect_u(text, text) TO regress_dblink_user;
@@ -938,7 +937,6 @@ DROP SERVER fdtest;
 -- should fail
 ALTER FOREIGN DATA WRAPPER dblink_fdw OPTIONS (nonexistent 'fdw');
 ERROR:  invalid option "nonexistent"
-HINT:  There are no valid options in this context.
 -- test asynchronous notifications
 SELECT dblink_connect(connection_parameters());
  dblink_connect 
diff --git a/contrib/file_fdw/expected/file_fdw.out b/contrib/file_fdw/expected/file_fdw.out
index 261af1a8b5..5cab3fa307 100644
--- a/contrib/file_fdw/expected/file_fdw.out
+++ b/contrib/file_fdw/expected/file_fdw.out
@@ -157,29 +157,21 @@ ALTER FOREIGN TABLE text_csv ALTER COLUMN word3 OPTIONS (force_not_null 'true');
 -- force_not_null is not allowed to be specified at any foreign object level:
 ALTER FOREIGN DATA WRAPPER file_fdw OPTIONS (ADD force_not_null '*'); -- ERROR
 ERROR:  invalid option "force_not_null"
-HINT:  There are no valid options in this context.
 ALTER SERVER file_server OPTIONS (ADD force_not_null '*'); -- ERROR
 ERROR:  invalid option "force_not_null"
-HINT:  There are no valid options in this context.
 CREATE USER MAPPING FOR public SERVER file_server OPTIONS (force_not_null '*'); -- ERROR
 ERROR:  invalid option "force_not_null"
-HINT:  There are no valid options in this context.
 CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (force_not_null '*'); -- ERROR
 ERROR:  invalid option "force_not_null"
-HINT:  Valid options in this context are: filename, program, format, header, delimiter, quote, escape, null, encoding
 -- force_null is not allowed to be specified at any foreign object level:
 ALTER FOREIGN DATA WRAPPER file_fdw OPTIONS (ADD force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
-HINT:  There are no valid options in this context.
 ALTER SERVER file_server OPTIONS (ADD force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
-HINT:  There are no valid options in this context.
 CREATE USER MAPPING FOR public SERVER file_server OPTIONS (force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
-HINT:  There are no valid options in this context.
 CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
-HINT:  Valid options in this context are: filename, program, format, header, delimiter, quote, escape, null, encoding
 -- basic query tests
 SELECT * FROM agg_text WHERE b > 10.0 ORDER BY a;
   a  |   b    
diff --git a/contrib/file_fdw/file_fdw.c b/contrib/file_fdw/file_fdw.c
index 4773cadec0..c5153346aa 100644
--- a/contrib/file_fdw/file_fdw.c
+++ b/contrib/file_fdw/file_fdw.c
@@ -212,30 +212,9 @@ file_fdw_validator(PG_FUNCTION_ARGS)
 		DefElem    *def = (DefElem *) lfirst(cell);
 
 		if (!is_valid_option(def->defname, catalog))
-		{
-			const struct FileFdwOption *opt;
-			StringInfoData buf;
-
-			/*
-			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
-			 */
-			initStringInfo(&buf);
-			for (opt = valid_options; opt->optname; opt++)
-			{
-				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->optname);
-			}
-
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
-					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
-		}
+					 errmsg("invalid option \"%s\"", def->defname)));
 
 		/*
 		 * Separate out filename, program, and column-specific options, since
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index a42c9720c3..f8e0163b4d 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -188,7 +188,6 @@ ALTER USER MAPPING FOR public SERVER testserver1
 ALTER USER MAPPING FOR public SERVER testserver1
 	OPTIONS (ADD sslmode 'require');
 ERROR:  invalid option "sslmode"
-HINT:  Valid options in this context are: user, password, sslpassword, password_required, sslcert, sslkey
 -- But we can add valid ones fine
 ALTER USER MAPPING FOR public SERVER testserver1
 	OPTIONS (ADD sslpassword 'dummy');
@@ -9623,7 +9622,6 @@ DETAIL:  Non-superusers must provide a password in the user mapping.
 -- in connstrs only in user mappings.
 ALTER SERVER loopback_nopw OPTIONS (ADD password 'dummypw');
 ERROR:  invalid option "password"
-HINT:  Valid options in this context are: service, passfile, channel_binding, connect_timeout, dbname, host, hostaddr, port, options, application_name, keepalives, keepalives_idle, keepalives_interval, keepalives_count, tcp_user_timeout, sslmode, sslcompression, sslcert, sslkey, sslrootcert, sslcrl, sslcrldir, sslsni, requirepeer, ssl_min_protocol_version, ssl_max_protocol_version, gssencmode, krbsrvname, gsslib, target_session_attrs, use_remote_estimate, fdw_startup_cost, fdw_tuple_cost, extensions, updatable, truncatable, fetch_size, batch_size, async_capable, parallel_commit, keep_connections
 -- If we add a password for our user mapping instead, we should get a different
 -- error because the password wasn't actually *used* when we run with trust auth.
 --
@@ -11237,7 +11235,6 @@ ERROR:  invalid value for integer option "batch_size": 100$%$#$#
 -- No option is allowed to be specified at foreign data wrapper level
 ALTER FOREIGN DATA WRAPPER postgres_fdw OPTIONS (nonexistent 'fdw');
 ERROR:  invalid option "nonexistent"
-HINT:  There are no valid options in this context.
 -- ===================================================================
 -- test postgres_fdw.application_name GUC
 -- ===================================================================
diff --git a/contrib/postgres_fdw/option.c b/contrib/postgres_fdw/option.c
index 95dde056eb..56d443e4f9 100644
--- a/contrib/postgres_fdw/option.c
+++ b/contrib/postgres_fdw/option.c
@@ -87,30 +87,9 @@ postgres_fdw_validator(PG_FUNCTION_ARGS)
 		DefElem    *def = (DefElem *) lfirst(cell);
 
 		if (!is_valid_option(def->defname, catalog))
-		{
-			/*
-			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
-			 */
-			PgFdwOption *opt;
-			StringInfoData buf;
-
-			initStringInfo(&buf);
-			for (opt = postgres_fdw_options; opt->keyword; opt++)
-			{
-				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->keyword);
-			}
-
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
-					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
-		}
+					 errmsg("invalid option \"%s\"", def->defname)));
 
 		/*
 		 * Validate option value, when we can do so without any context.
diff --git a/src/backend/foreign/foreign.c b/src/backend/foreign/foreign.c
index cf222fc3e9..194dbea5c4 100644
--- a/src/backend/foreign/foreign.c
+++ b/src/backend/foreign/foreign.c
@@ -620,26 +620,9 @@ postgresql_fdw_validator(PG_FUNCTION_ARGS)
 
 		if (!is_conninfo_option(def->defname, catalog))
 		{
-			const struct ConnectionOption *opt;
-			StringInfoData buf;
-
-			/*
-			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
-			 */
-			initStringInfo(&buf);
-			for (opt = libpq_conninfo_options; opt->optname; opt++)
-				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->optname);
-
 			ereport(ERROR,
 					(errcode(ERRCODE_SYNTAX_ERROR),
-					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 errmsg("invalid option \"%s\"", def->defname)));
 
 			PG_RETURN_BOOL(false);
 		}
diff --git a/src/test/regress/expected/foreign_data.out b/src/test/regress/expected/foreign_data.out
index 33505352cc..ae0c7a5c18 100644
--- a/src/test/regress/expected/foreign_data.out
+++ b/src/test/regress/expected/foreign_data.out
@@ -110,7 +110,6 @@ DROP FOREIGN DATA WRAPPER test_fdw;
 -- ALTER FOREIGN DATA WRAPPER
 ALTER FOREIGN DATA WRAPPER foo OPTIONS (nonexistent 'fdw');         -- ERROR
 ERROR:  invalid option "nonexistent"
-HINT:  There are no valid options in this context.
 ALTER FOREIGN DATA WRAPPER foo;                             -- ERROR
 ERROR:  syntax error at or near ";"
 LINE 1: ALTER FOREIGN DATA WRAPPER foo;
@@ -329,7 +328,6 @@ CREATE SERVER s6 VERSION '16.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbna
 CREATE SERVER s7 TYPE 'oracle' VERSION '17.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbname 'b');
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (foo '1'); -- ERROR
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (host 'localhost', dbname 's8db');
 \des+
                                                              List of foreign servers
@@ -440,7 +438,6 @@ ERROR:  permission denied for foreign-data wrapper foo
 RESET ROLE;
 ALTER SERVER s8 OPTIONS (foo '1');                          -- ERROR option validation
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
 ALTER SERVER s8 OPTIONS (connect_timeout '30', SET dbname 'db1', DROP host);
 SET ROLE regress_test_role;
 ALTER SERVER s1 OWNER TO regress_test_indirect;             -- ERROR
@@ -597,7 +594,6 @@ ERROR:  user mapping for "regress_foreign_data_user" already exists for server "
 CREATE USER MAPPING FOR public SERVER s4 OPTIONS ("this mapping" 'is public');
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (username 'test', password 'secret');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (user 'test', password 'secret');
 ALTER SERVER s5 OWNER TO regress_test_role;
 ALTER SERVER s6 OWNER TO regress_test_indirect;
@@ -636,7 +632,6 @@ ALTER USER MAPPING FOR public SERVER s5 OPTIONS (gotcha 'true');            -- E
 ERROR:  user mapping for "public" does not exist for server "s5"
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (username 'test');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (DROP user, SET password 'public');
 SET ROLE regress_test_role;
 ALTER USER MAPPING FOR current_user SERVER s5 OPTIONS (ADD modified '1');
-- 
2.37.1

diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
index e323fdd0e6..7fe42cb732 100644
--- a/contrib/dblink/dblink.c
+++ b/contrib/dblink/dblink.c
@@ -2006,28 +2006,31 @@ dblink_fdw_validator(PG_FUNCTION_ARGS)
 
 		if (!is_valid_dblink_option(options, def->defname, context))
 		{
-			/*
-			 * Unknown option, or invalid option for the context specified, so
-			 * complain about it.  Provide a hint with list of valid options
-			 * for the context.
-			 */
-			StringInfoData buf;
-			const PQconninfoOption *opt;
+			int	min_dist = -1;
+			char *hint = NULL;
 
-			initStringInfo(&buf);
-			for (opt = options; opt->keyword; opt++)
+			for (const PQconninfoOption *opt = options; opt->keyword; opt++)
 			{
 				if (is_valid_dblink_option(options, opt->keyword, context))
-					appendStringInfo(&buf, "%s%s",
-									 (buf.len > 0) ? ", " : "",
-									 opt->keyword);
+				{
+					int dist;
+
+					dist = varstr_levenshtein(def->defname, strlen(def->defname),
+											  opt->keyword, strlen(opt->keyword),
+											  1, 1, 1, false);
+					if (min_dist == -1 || dist < min_dist)
+					{
+						min_dist = dist;
+						hint = opt->keyword;
+					}
+				}
 			}
+
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_OPTION_NAME_NOT_FOUND),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
+					 hint != NULL
+					 ? errhint("Did you mean \"%s\"?", hint)
 					 : errhint("There are no valid options in this context.")));
 		}
 	}
diff --git a/contrib/dblink/expected/dblink.out b/contrib/dblink/expected/dblink.out
index c7bde6ad07..2b874fc450 100644
--- a/contrib/dblink/expected/dblink.out
+++ b/contrib/dblink/expected/dblink.out
@@ -897,7 +897,7 @@ $d$;
 CREATE USER MAPPING FOR public SERVER fdtest
   OPTIONS (server 'localhost');  -- fail, can't specify server here
 ERROR:  invalid option "server"
-HINT:  Valid options in this context are: user, password, sslpassword
+HINT:  Did you mean "user"?
 CREATE USER MAPPING FOR public SERVER fdtest OPTIONS (user :'USER');
 GRANT USAGE ON FOREIGN SERVER fdtest TO regress_dblink_user;
 GRANT EXECUTE ON FUNCTION dblink_connect_u(text, text) TO regress_dblink_user;
diff --git a/contrib/file_fdw/expected/file_fdw.out b/contrib/file_fdw/expected/file_fdw.out
index 261af1a8b5..b780b1a13c 100644
--- a/contrib/file_fdw/expected/file_fdw.out
+++ b/contrib/file_fdw/expected/file_fdw.out
@@ -166,7 +166,7 @@ ERROR:  invalid option "force_not_null"
 HINT:  There are no valid options in this context.
 CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (force_not_null '*'); -- ERROR
 ERROR:  invalid option "force_not_null"
-HINT:  Valid options in this context are: filename, program, format, header, delimiter, quote, escape, null, encoding
+HINT:  Did you mean "format"?
 -- force_null is not allowed to be specified at any foreign object level:
 ALTER FOREIGN DATA WRAPPER file_fdw OPTIONS (ADD force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
@@ -179,7 +179,7 @@ ERROR:  invalid option "force_null"
 HINT:  There are no valid options in this context.
 CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
-HINT:  Valid options in this context are: filename, program, format, header, delimiter, quote, escape, null, encoding
+HINT:  Did you mean "null"?
 -- basic query tests
 SELECT * FROM agg_text WHERE b > 10.0 ORDER BY a;
   a  |   b    
diff --git a/contrib/file_fdw/file_fdw.c b/contrib/file_fdw/file_fdw.c
index 4773cadec0..49dec5b7bf 100644
--- a/contrib/file_fdw/file_fdw.c
+++ b/contrib/file_fdw/file_fdw.c
@@ -37,6 +37,7 @@
 #include "utils/memutils.h"
 #include "utils/rel.h"
 #include "utils/sampling.h"
+#include "utils/varlena.h"
 
 PG_MODULE_MAGIC;
 
@@ -213,27 +214,31 @@ file_fdw_validator(PG_FUNCTION_ARGS)
 
 		if (!is_valid_option(def->defname, catalog))
 		{
-			const struct FileFdwOption *opt;
-			StringInfoData buf;
+			int min_dist = -1;
+			const char *hint = NULL;
 
-			/*
-			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
-			 */
-			initStringInfo(&buf);
-			for (opt = valid_options; opt->optname; opt++)
+			for (const struct FileFdwOption *opt = valid_options; opt->optname; opt++)
 			{
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->optname);
+				{
+					int dist;
+
+					dist = varstr_levenshtein(def->defname, strlen(def->defname),
+											  opt->optname, strlen(opt->optname),
+											  1, 1, 1, false);
+					if (min_dist == -1 || dist < min_dist)
+					{
+						min_dist = dist;
+						hint = opt->optname;
+					}
+				}
 			}
 
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
+					 hint != NULL
+					 ? errhint("Did you mean \"%s\"?", hint)
 					 : errhint("There are no valid options in this context.")));
 		}
 
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 7bf35602b0..036eaa63df 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -188,7 +188,7 @@ ALTER USER MAPPING FOR public SERVER testserver1
 ALTER USER MAPPING FOR public SERVER testserver1
 	OPTIONS (ADD sslmode 'require');
 ERROR:  invalid option "sslmode"
-HINT:  Valid options in this context are: user, password, sslpassword, password_required, sslcert, sslkey
+HINT:  Did you mean "sslcert"?
 -- But we can add valid ones fine
 ALTER USER MAPPING FOR public SERVER testserver1
 	OPTIONS (ADD sslpassword 'dummy');
@@ -9627,7 +9627,7 @@ DO $d$
     END;
 $d$;
 ERROR:  invalid option "password"
-HINT:  Valid options in this context are: service, passfile, channel_binding, connect_timeout, dbname, host, hostaddr, port, options, application_name, keepalives, keepalives_idle, keepalives_interval, keepalives_count, tcp_user_timeout, sslmode, sslcompression, sslcert, sslkey, sslrootcert, sslcrl, sslcrldir, sslsni, requirepeer, ssl_min_protocol_version, ssl_max_protocol_version, gssencmode, krbsrvname, gsslib, target_session_attrs, use_remote_estimate, fdw_startup_cost, fdw_tuple_cost, extensions, updatable, truncatable, fetch_size, batch_size, async_capable, parallel_commit, keep_connections
+HINT:  Did you mean "passfile"?
 CONTEXT:  SQL statement "ALTER SERVER loopback_nopw OPTIONS (ADD password 'dummypw')"
 PL/pgSQL function inline_code_block line 3 at EXECUTE
 -- If we add a password for our user mapping instead, we should get a different
diff --git a/contrib/postgres_fdw/option.c b/contrib/postgres_fdw/option.c
index 95dde056eb..fe8a3e79f9 100644
--- a/contrib/postgres_fdw/option.c
+++ b/contrib/postgres_fdw/option.c
@@ -88,27 +88,31 @@ postgres_fdw_validator(PG_FUNCTION_ARGS)
 
 		if (!is_valid_option(def->defname, catalog))
 		{
-			/*
-			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
-			 */
-			PgFdwOption *opt;
-			StringInfoData buf;
+			int min_dist = -1;
+			const char *hint = NULL;
 
-			initStringInfo(&buf);
-			for (opt = postgres_fdw_options; opt->keyword; opt++)
+			for (PgFdwOption *opt = postgres_fdw_options; opt->keyword; opt++)
 			{
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->keyword);
+				{
+					int dist;
+
+					dist = varstr_levenshtein(def->defname, strlen(def->defname),
+											  opt->keyword, strlen(opt->keyword),
+											  1, 1, 1, false);
+					if (min_dist == -1 || dist < min_dist)
+					{
+						min_dist = dist;
+						hint = opt->keyword;
+					}
+				}
 			}
 
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
+					 hint != NULL
+					 ? errhint("Did you mean \"%s\"?", hint)
 					 : errhint("There are no valid options in this context.")));
 		}
 
diff --git a/src/backend/foreign/foreign.c b/src/backend/foreign/foreign.c
index cf222fc3e9..a84116144e 100644
--- a/src/backend/foreign/foreign.c
+++ b/src/backend/foreign/foreign.c
@@ -27,6 +27,7 @@
 #include "utils/memutils.h"
 #include "utils/rel.h"
 #include "utils/syscache.h"
+#include "utils/varlena.h"
 
 
 /*
@@ -620,25 +621,29 @@ postgresql_fdw_validator(PG_FUNCTION_ARGS)
 
 		if (!is_conninfo_option(def->defname, catalog))
 		{
-			const struct ConnectionOption *opt;
-			StringInfoData buf;
-
-			/*
-			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
-			 */
-			initStringInfo(&buf);
-			for (opt = libpq_conninfo_options; opt->optname; opt++)
+			int min_dist = -1;
+			const char *hint = NULL;
+
+			for (const struct ConnectionOption *opt = libpq_conninfo_options; opt->optname; opt++)
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->optname);
+				{
+					int dist;
+
+					dist = varstr_levenshtein(def->defname, strlen(def->defname),
+											  opt->optname, strlen(opt->optname),
+											  1, 1, 1, false);
+					if (min_dist == -1 || dist < min_dist)
+					{
+						min_dist = dist;
+						hint = opt->optname;
+					}
+				}
 
 			ereport(ERROR,
 					(errcode(ERRCODE_SYNTAX_ERROR),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
+					 hint != NULL
+					 ? errhint("Did you mean \"%s\"?", hint)
 					 : errhint("There are no valid options in this context.")));
 
 			PG_RETURN_BOOL(false);
diff --git a/src/test/regress/expected/foreign_data.out b/src/test/regress/expected/foreign_data.out
index 33505352cc..588ce62266 100644
--- a/src/test/regress/expected/foreign_data.out
+++ b/src/test/regress/expected/foreign_data.out
@@ -329,7 +329,7 @@ CREATE SERVER s6 VERSION '16.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbna
 CREATE SERVER s7 TYPE 'oracle' VERSION '17.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbname 'b');
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (foo '1'); -- ERROR
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
+HINT:  Did you mean "host"?
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (host 'localhost', dbname 's8db');
 \des+
                                                              List of foreign servers
@@ -440,7 +440,7 @@ ERROR:  permission denied for foreign-data wrapper foo
 RESET ROLE;
 ALTER SERVER s8 OPTIONS (foo '1');                          -- ERROR option validation
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
+HINT:  Did you mean "host"?
 ALTER SERVER s8 OPTIONS (connect_timeout '30', SET dbname 'db1', DROP host);
 SET ROLE regress_test_role;
 ALTER SERVER s1 OWNER TO regress_test_indirect;             -- ERROR
@@ -597,7 +597,7 @@ ERROR:  user mapping for "regress_foreign_data_user" already exists for server "
 CREATE USER MAPPING FOR public SERVER s4 OPTIONS ("this mapping" 'is public');
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (username 'test', password 'secret');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Did you mean "user"?
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (user 'test', password 'secret');
 ALTER SERVER s5 OWNER TO regress_test_role;
 ALTER SERVER s6 OWNER TO regress_test_indirect;
@@ -636,7 +636,7 @@ ALTER USER MAPPING FOR public SERVER s5 OPTIONS (gotcha 'true');            -- E
 ERROR:  user mapping for "public" does not exist for server "s5"
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (username 'test');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Did you mean "user"?
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (DROP user, SET password 'public');
 SET ROLE regress_test_role;
 ALTER USER MAPPING FOR current_user SERVER s5 OPTIONS (ADD modified '1');

From c3c7793daf7e6b225605a44a1faead2f7678bca3 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandbossart@gmail.com>
Date: Fri, 2 Sep 2022 14:03:26 -0700
Subject: [PATCH v2 1/1] Adjust assorted hint messages that list all valid
 options.

Instead of listing all valid options, we now try to provide one
that looks similar.  Since this may be useful elsewhere, this
change introduces a new set of functions that can be reused for
similar purposes.
---
 contrib/dblink/dblink.c                       | 26 +++---
 contrib/dblink/expected/dblink.out            |  2 +-
 contrib/file_fdw/expected/file_fdw.out        |  2 -
 contrib/file_fdw/file_fdw.c                   | 23 ++++--
 .../postgres_fdw/expected/postgres_fdw.out    |  4 +-
 contrib/postgres_fdw/option.c                 | 22 +++--
 src/backend/foreign/foreign.c                 | 25 ++++--
 src/backend/utils/adt/varlena.c               | 82 +++++++++++++++++++
 src/include/utils/varlena.h                   | 12 +++
 src/test/regress/expected/foreign_data.out    |  8 +-
 10 files changed, 159 insertions(+), 47 deletions(-)

diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
index e323fdd0e6..c134f73adb 100644
--- a/contrib/dblink/dblink.c
+++ b/contrib/dblink/dblink.c
@@ -2008,27 +2008,31 @@ dblink_fdw_validator(PG_FUNCTION_ARGS)
 		{
 			/*
 			 * Unknown option, or invalid option for the context specified, so
-			 * complain about it.  Provide a hint with list of valid options
-			 * for the context.
+			 * complain about it.  Provide a hint with a valid option that
+			 * looks similar, if there is one.
 			 */
-			StringInfoData buf;
 			const PQconninfoOption *opt;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 5);
 			for (opt = options; opt->keyword; opt++)
 			{
 				if (is_valid_dblink_option(options, opt->keyword, context))
-					appendStringInfo(&buf, "%s%s",
-									 (buf.len > 0) ? ", " : "",
-									 opt->keyword);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->keyword);
+				}
 			}
+
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_OPTION_NAME_NOT_FOUND),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Did you mean \"%s\"?", closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 		}
 	}
 
diff --git a/contrib/dblink/expected/dblink.out b/contrib/dblink/expected/dblink.out
index c7bde6ad07..2b874fc450 100644
--- a/contrib/dblink/expected/dblink.out
+++ b/contrib/dblink/expected/dblink.out
@@ -897,7 +897,7 @@ $d$;
 CREATE USER MAPPING FOR public SERVER fdtest
   OPTIONS (server 'localhost');  -- fail, can't specify server here
 ERROR:  invalid option "server"
-HINT:  Valid options in this context are: user, password, sslpassword
+HINT:  Did you mean "user"?
 CREATE USER MAPPING FOR public SERVER fdtest OPTIONS (user :'USER');
 GRANT USAGE ON FOREIGN SERVER fdtest TO regress_dblink_user;
 GRANT EXECUTE ON FUNCTION dblink_connect_u(text, text) TO regress_dblink_user;
diff --git a/contrib/file_fdw/expected/file_fdw.out b/contrib/file_fdw/expected/file_fdw.out
index 261af1a8b5..36d76ba26c 100644
--- a/contrib/file_fdw/expected/file_fdw.out
+++ b/contrib/file_fdw/expected/file_fdw.out
@@ -166,7 +166,6 @@ ERROR:  invalid option "force_not_null"
 HINT:  There are no valid options in this context.
 CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (force_not_null '*'); -- ERROR
 ERROR:  invalid option "force_not_null"
-HINT:  Valid options in this context are: filename, program, format, header, delimiter, quote, escape, null, encoding
 -- force_null is not allowed to be specified at any foreign object level:
 ALTER FOREIGN DATA WRAPPER file_fdw OPTIONS (ADD force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
@@ -179,7 +178,6 @@ ERROR:  invalid option "force_null"
 HINT:  There are no valid options in this context.
 CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
-HINT:  Valid options in this context are: filename, program, format, header, delimiter, quote, escape, null, encoding
 -- basic query tests
 SELECT * FROM agg_text WHERE b > 10.0 ORDER BY a;
   a  |   b    
diff --git a/contrib/file_fdw/file_fdw.c b/contrib/file_fdw/file_fdw.c
index 4773cadec0..e3b69ec125 100644
--- a/contrib/file_fdw/file_fdw.c
+++ b/contrib/file_fdw/file_fdw.c
@@ -37,6 +37,7 @@
 #include "utils/memutils.h"
 #include "utils/rel.h"
 #include "utils/sampling.h"
+#include "utils/varlena.h"
 
 PG_MODULE_MAGIC;
 
@@ -214,27 +215,31 @@ file_fdw_validator(PG_FUNCTION_ARGS)
 		if (!is_valid_option(def->defname, catalog))
 		{
 			const struct FileFdwOption *opt;
-			StringInfoData buf;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
 			/*
 			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
+			 * with a valid option that looks similar, if there is one.
 			 */
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 5);
 			for (opt = valid_options; opt->optname; opt++)
 			{
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->optname);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->optname);
+				}
 			}
 
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Did you mean \"%s\"?", closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 		}
 
 		/*
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 7bf35602b0..036eaa63df 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -188,7 +188,7 @@ ALTER USER MAPPING FOR public SERVER testserver1
 ALTER USER MAPPING FOR public SERVER testserver1
 	OPTIONS (ADD sslmode 'require');
 ERROR:  invalid option "sslmode"
-HINT:  Valid options in this context are: user, password, sslpassword, password_required, sslcert, sslkey
+HINT:  Did you mean "sslcert"?
 -- But we can add valid ones fine
 ALTER USER MAPPING FOR public SERVER testserver1
 	OPTIONS (ADD sslpassword 'dummy');
@@ -9627,7 +9627,7 @@ DO $d$
     END;
 $d$;
 ERROR:  invalid option "password"
-HINT:  Valid options in this context are: service, passfile, channel_binding, connect_timeout, dbname, host, hostaddr, port, options, application_name, keepalives, keepalives_idle, keepalives_interval, keepalives_count, tcp_user_timeout, sslmode, sslcompression, sslcert, sslkey, sslrootcert, sslcrl, sslcrldir, sslsni, requirepeer, ssl_min_protocol_version, ssl_max_protocol_version, gssencmode, krbsrvname, gsslib, target_session_attrs, use_remote_estimate, fdw_startup_cost, fdw_tuple_cost, extensions, updatable, truncatable, fetch_size, batch_size, async_capable, parallel_commit, keep_connections
+HINT:  Did you mean "passfile"?
 CONTEXT:  SQL statement "ALTER SERVER loopback_nopw OPTIONS (ADD password 'dummypw')"
 PL/pgSQL function inline_code_block line 3 at EXECUTE
 -- If we add a password for our user mapping instead, we should get a different
diff --git a/contrib/postgres_fdw/option.c b/contrib/postgres_fdw/option.c
index 95dde056eb..5ac0484c3e 100644
--- a/contrib/postgres_fdw/option.c
+++ b/contrib/postgres_fdw/option.c
@@ -90,26 +90,30 @@ postgres_fdw_validator(PG_FUNCTION_ARGS)
 		{
 			/*
 			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
+			 * with a valid option that looks similar, if there is one.
 			 */
 			PgFdwOption *opt;
-			StringInfoData buf;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 5);
 			for (opt = postgres_fdw_options; opt->keyword; opt++)
 			{
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->keyword);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->keyword);
+				}
 			}
 
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Did you mean \"%s\"?", closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 		}
 
 		/*
diff --git a/src/backend/foreign/foreign.c b/src/backend/foreign/foreign.c
index cf222fc3e9..0e2004ec8c 100644
--- a/src/backend/foreign/foreign.c
+++ b/src/backend/foreign/foreign.c
@@ -27,6 +27,7 @@
 #include "utils/memutils.h"
 #include "utils/rel.h"
 #include "utils/syscache.h"
+#include "utils/varlena.h"
 
 
 /*
@@ -621,25 +622,31 @@ postgresql_fdw_validator(PG_FUNCTION_ARGS)
 		if (!is_conninfo_option(def->defname, catalog))
 		{
 			const struct ConnectionOption *opt;
-			StringInfoData buf;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
 			/*
 			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
+			 * with a valid option that looks similar, if there is one.
 			 */
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 5);
 			for (opt = libpq_conninfo_options; opt->optname; opt++)
+			{
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->optname);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->optname);
+				}
+			}
 
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_SYNTAX_ERROR),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Did you mean \"%s\"?", closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 
 			PG_RETURN_BOOL(false);
 		}
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index 8539cef024..55905c5f5d 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -6196,6 +6196,88 @@ rest_of_char_same(const char *s1, const char *s2, int len)
 #include "levenshtein.c"
 
 
+/*
+ * The following *ClosestMatch() functions can be used to determine whether a
+ * user-provided string resembles any known valid values, which is useful for
+ * providing hints in log messages, among other things.  Use these functions
+ * like so:
+ *
+ *		initClosestMatch(&state, source_string, max_distance);
+ *
+ *		for (int i = 0; i < num_valid_strings; i++)
+ *			updateClosestMatch(&state, valid_strings[i]);
+ *
+ *		closestMatch = getClosestMatch(&state);
+ */
+
+/*
+ * Initialize the given state with the source string and maximum Levenshtein
+ * distance to consider.
+ */
+void
+initClosestMatch(ClosestMatchState *state, const char *source, int max_d)
+{
+	Assert(state);
+	Assert(max_d >= 0);
+
+	state->source = source;
+	state->min_d = -1;
+	state->max_d = max_d;
+	state->match = NULL;
+}
+
+/*
+ * If the candidate string is a closer match than the current one saved (or
+ * there is no match saved), save it as the closest match.
+ *
+ * If the source or candidate string is NULL, empty, or too long, this function
+ * takes no action.  Likewise, if the Levenshtein distance between the source
+ * string and the candidate string exceeds the maximum distance allowed by the
+ * state, no action is taken.
+ */
+void
+updateClosestMatch(ClosestMatchState *state, const char *candidate)
+{
+	int			dist;
+
+	Assert(state);
+
+	if (state->source == NULL || state->source[0] == '\0' ||
+		candidate == NULL || candidate[0] == '\0')
+		return;
+
+	/*
+	 * To avoid ERROR-ing, we check the lengths here instead of setting
+	 * 'trusted' to false in the call to varstr_levenshtein_less_equal().
+	 */
+	if (strlen(state->source) > MAX_LEVENSHTEIN_STRLEN ||
+		strlen(candidate) > MAX_LEVENSHTEIN_STRLEN)
+		return;
+
+	dist = varstr_levenshtein_less_equal(state->source, strlen(state->source),
+										 candidate, strlen(candidate), 1, 1, 1,
+										 state->max_d, true);
+	if (dist <= state->max_d &&
+		(state->min_d == -1 || dist < state->min_d))
+	{
+		state->min_d = dist;
+		state->match = candidate;
+	}
+}
+
+/*
+ * Return the closest match.  If no suitable candidates were provided via
+ * updateClosestMatch(), return NULL.
+ */
+const char *
+getClosestMatch(ClosestMatchState *state)
+{
+	Assert(state);
+
+	return state->match;
+}
+
+
 /*
  * Unicode support
  */
diff --git a/src/include/utils/varlena.h b/src/include/utils/varlena.h
index c45208a204..2bc3b6e519 100644
--- a/src/include/utils/varlena.h
+++ b/src/include/utils/varlena.h
@@ -38,4 +38,16 @@ extern text *replace_text_regexp(text *src_text, text *pattern_text,
 								 int cflags, Oid collation,
 								 int search_start, int n);
 
+typedef struct ClosestMatchState
+{
+	const char *source;
+	int min_d;
+	int max_d;
+	const char *match;
+} ClosestMatchState;
+
+extern void initClosestMatch(ClosestMatchState *state, const char *source, int max_d);
+extern void updateClosestMatch(ClosestMatchState *state, const char *candidate);
+extern const char *getClosestMatch(ClosestMatchState *state);
+
 #endif
diff --git a/src/test/regress/expected/foreign_data.out b/src/test/regress/expected/foreign_data.out
index 33505352cc..588ce62266 100644
--- a/src/test/regress/expected/foreign_data.out
+++ b/src/test/regress/expected/foreign_data.out
@@ -329,7 +329,7 @@ CREATE SERVER s6 VERSION '16.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbna
 CREATE SERVER s7 TYPE 'oracle' VERSION '17.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbname 'b');
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (foo '1'); -- ERROR
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
+HINT:  Did you mean "host"?
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (host 'localhost', dbname 's8db');
 \des+
                                                              List of foreign servers
@@ -440,7 +440,7 @@ ERROR:  permission denied for foreign-data wrapper foo
 RESET ROLE;
 ALTER SERVER s8 OPTIONS (foo '1');                          -- ERROR option validation
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
+HINT:  Did you mean "host"?
 ALTER SERVER s8 OPTIONS (connect_timeout '30', SET dbname 'db1', DROP host);
 SET ROLE regress_test_role;
 ALTER SERVER s1 OWNER TO regress_test_indirect;             -- ERROR
@@ -597,7 +597,7 @@ ERROR:  user mapping for "regress_foreign_data_user" already exists for server "
 CREATE USER MAPPING FOR public SERVER s4 OPTIONS ("this mapping" 'is public');
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (username 'test', password 'secret');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Did you mean "user"?
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (user 'test', password 'secret');
 ALTER SERVER s5 OWNER TO regress_test_role;
 ALTER SERVER s6 OWNER TO regress_test_indirect;
@@ -636,7 +636,7 @@ ALTER USER MAPPING FOR public SERVER s5 OPTIONS (gotcha 'true');            -- E
 ERROR:  user mapping for "public" does not exist for server "s5"
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (username 'test');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Did you mean "user"?
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (DROP user, SET password 'public');
 SET ROLE regress_test_role;
 ALTER USER MAPPING FOR current_user SERVER s5 OPTIONS (ADD modified '1');
-- 
2.25.1

From 1ce0024357343cf4c1436cd74ed20e304d673762 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandbossart@gmail.com>
Date: Fri, 2 Sep 2022 14:03:26 -0700
Subject: [PATCH v3 1/1] Adjust assorted hint messages that list all valid
 options.

Instead of listing all valid options, we now try to provide one
that looks similar.  Since this may be useful elsewhere, this
change introduces a new set of functions that can be reused for
similar purposes.
---
 contrib/dblink/dblink.c                       | 26 +++---
 contrib/dblink/expected/dblink.out            |  1 -
 contrib/file_fdw/expected/file_fdw.out        |  2 -
 contrib/file_fdw/file_fdw.c                   | 23 ++++--
 .../postgres_fdw/expected/postgres_fdw.out    |  3 +-
 contrib/postgres_fdw/option.c                 | 22 +++--
 src/backend/foreign/foreign.c                 | 25 ++++--
 src/backend/utils/adt/varlena.c               | 82 +++++++++++++++++++
 src/include/utils/varlena.h                   | 12 +++
 src/test/regress/expected/foreign_data.out    |  6 +-
 10 files changed, 155 insertions(+), 47 deletions(-)

diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
index e323fdd0e6..5e2d7b4c70 100644
--- a/contrib/dblink/dblink.c
+++ b/contrib/dblink/dblink.c
@@ -2008,27 +2008,31 @@ dblink_fdw_validator(PG_FUNCTION_ARGS)
 		{
 			/*
 			 * Unknown option, or invalid option for the context specified, so
-			 * complain about it.  Provide a hint with list of valid options
-			 * for the context.
+			 * complain about it.  Provide a hint with a valid option that
+			 * looks similar, if there is one.
 			 */
-			StringInfoData buf;
 			const PQconninfoOption *opt;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 4);
 			for (opt = options; opt->keyword; opt++)
 			{
 				if (is_valid_dblink_option(options, opt->keyword, context))
-					appendStringInfo(&buf, "%s%s",
-									 (buf.len > 0) ? ", " : "",
-									 opt->keyword);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->keyword);
+				}
 			}
+
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_OPTION_NAME_NOT_FOUND),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Did you mean \"%s\"?", closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 		}
 	}
 
diff --git a/contrib/dblink/expected/dblink.out b/contrib/dblink/expected/dblink.out
index c7bde6ad07..14d015e4d5 100644
--- a/contrib/dblink/expected/dblink.out
+++ b/contrib/dblink/expected/dblink.out
@@ -897,7 +897,6 @@ $d$;
 CREATE USER MAPPING FOR public SERVER fdtest
   OPTIONS (server 'localhost');  -- fail, can't specify server here
 ERROR:  invalid option "server"
-HINT:  Valid options in this context are: user, password, sslpassword
 CREATE USER MAPPING FOR public SERVER fdtest OPTIONS (user :'USER');
 GRANT USAGE ON FOREIGN SERVER fdtest TO regress_dblink_user;
 GRANT EXECUTE ON FUNCTION dblink_connect_u(text, text) TO regress_dblink_user;
diff --git a/contrib/file_fdw/expected/file_fdw.out b/contrib/file_fdw/expected/file_fdw.out
index 261af1a8b5..36d76ba26c 100644
--- a/contrib/file_fdw/expected/file_fdw.out
+++ b/contrib/file_fdw/expected/file_fdw.out
@@ -166,7 +166,6 @@ ERROR:  invalid option "force_not_null"
 HINT:  There are no valid options in this context.
 CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (force_not_null '*'); -- ERROR
 ERROR:  invalid option "force_not_null"
-HINT:  Valid options in this context are: filename, program, format, header, delimiter, quote, escape, null, encoding
 -- force_null is not allowed to be specified at any foreign object level:
 ALTER FOREIGN DATA WRAPPER file_fdw OPTIONS (ADD force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
@@ -179,7 +178,6 @@ ERROR:  invalid option "force_null"
 HINT:  There are no valid options in this context.
 CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
-HINT:  Valid options in this context are: filename, program, format, header, delimiter, quote, escape, null, encoding
 -- basic query tests
 SELECT * FROM agg_text WHERE b > 10.0 ORDER BY a;
   a  |   b    
diff --git a/contrib/file_fdw/file_fdw.c b/contrib/file_fdw/file_fdw.c
index 4773cadec0..53d996bd7c 100644
--- a/contrib/file_fdw/file_fdw.c
+++ b/contrib/file_fdw/file_fdw.c
@@ -37,6 +37,7 @@
 #include "utils/memutils.h"
 #include "utils/rel.h"
 #include "utils/sampling.h"
+#include "utils/varlena.h"
 
 PG_MODULE_MAGIC;
 
@@ -214,27 +215,31 @@ file_fdw_validator(PG_FUNCTION_ARGS)
 		if (!is_valid_option(def->defname, catalog))
 		{
 			const struct FileFdwOption *opt;
-			StringInfoData buf;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
 			/*
 			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
+			 * with a valid option that looks similar, if there is one.
 			 */
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 4);
 			for (opt = valid_options; opt->optname; opt++)
 			{
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->optname);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->optname);
+				}
 			}
 
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Did you mean \"%s\"?", closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 		}
 
 		/*
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 7bf35602b0..2588ad4aa6 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -188,7 +188,6 @@ ALTER USER MAPPING FOR public SERVER testserver1
 ALTER USER MAPPING FOR public SERVER testserver1
 	OPTIONS (ADD sslmode 'require');
 ERROR:  invalid option "sslmode"
-HINT:  Valid options in this context are: user, password, sslpassword, password_required, sslcert, sslkey
 -- But we can add valid ones fine
 ALTER USER MAPPING FOR public SERVER testserver1
 	OPTIONS (ADD sslpassword 'dummy');
@@ -9627,7 +9626,7 @@ DO $d$
     END;
 $d$;
 ERROR:  invalid option "password"
-HINT:  Valid options in this context are: service, passfile, channel_binding, connect_timeout, dbname, host, hostaddr, port, options, application_name, keepalives, keepalives_idle, keepalives_interval, keepalives_count, tcp_user_timeout, sslmode, sslcompression, sslcert, sslkey, sslrootcert, sslcrl, sslcrldir, sslsni, requirepeer, ssl_min_protocol_version, ssl_max_protocol_version, gssencmode, krbsrvname, gsslib, target_session_attrs, use_remote_estimate, fdw_startup_cost, fdw_tuple_cost, extensions, updatable, truncatable, fetch_size, batch_size, async_capable, parallel_commit, keep_connections
+HINT:  Did you mean "passfile"?
 CONTEXT:  SQL statement "ALTER SERVER loopback_nopw OPTIONS (ADD password 'dummypw')"
 PL/pgSQL function inline_code_block line 3 at EXECUTE
 -- If we add a password for our user mapping instead, we should get a different
diff --git a/contrib/postgres_fdw/option.c b/contrib/postgres_fdw/option.c
index 95dde056eb..6971c88463 100644
--- a/contrib/postgres_fdw/option.c
+++ b/contrib/postgres_fdw/option.c
@@ -90,26 +90,30 @@ postgres_fdw_validator(PG_FUNCTION_ARGS)
 		{
 			/*
 			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
+			 * with a valid option that looks similar, if there is one.
 			 */
 			PgFdwOption *opt;
-			StringInfoData buf;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 4);
 			for (opt = postgres_fdw_options; opt->keyword; opt++)
 			{
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->keyword);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->keyword);
+				}
 			}
 
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Did you mean \"%s\"?", closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 		}
 
 		/*
diff --git a/src/backend/foreign/foreign.c b/src/backend/foreign/foreign.c
index cf222fc3e9..283ebb6a58 100644
--- a/src/backend/foreign/foreign.c
+++ b/src/backend/foreign/foreign.c
@@ -27,6 +27,7 @@
 #include "utils/memutils.h"
 #include "utils/rel.h"
 #include "utils/syscache.h"
+#include "utils/varlena.h"
 
 
 /*
@@ -621,25 +622,31 @@ postgresql_fdw_validator(PG_FUNCTION_ARGS)
 		if (!is_conninfo_option(def->defname, catalog))
 		{
 			const struct ConnectionOption *opt;
-			StringInfoData buf;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
 			/*
 			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
+			 * with a valid option that looks similar, if there is one.
 			 */
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 4);
 			for (opt = libpq_conninfo_options; opt->optname; opt++)
+			{
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->optname);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->optname);
+				}
+			}
 
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_SYNTAX_ERROR),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Did you mean \"%s\"?", closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 
 			PG_RETURN_BOOL(false);
 		}
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index 8539cef024..174f9c390d 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -6196,6 +6196,88 @@ rest_of_char_same(const char *s1, const char *s2, int len)
 #include "levenshtein.c"
 
 
+/*
+ * The following *ClosestMatch() functions can be used to determine whether a
+ * user-provided string resembles any known valid values, which is useful for
+ * providing hints in log messages, among other things.  Use these functions
+ * like so:
+ *
+ *		initClosestMatch(&state, source_string, max_distance);
+ *
+ *		for (int i = 0; i < num_valid_strings; i++)
+ *			updateClosestMatch(&state, valid_strings[i]);
+ *
+ *		closestMatch = getClosestMatch(&state);
+ */
+
+/*
+ * Initialize the given state with the source string and maximum Levenshtein
+ * distance to consider.
+ */
+void
+initClosestMatch(ClosestMatchState *state, const char *source, int max_d)
+{
+	Assert(state);
+	Assert(max_d >= 0);
+
+	state->source = source;
+	state->min_d = -1;
+	state->max_d = max_d;
+	state->match = NULL;
+}
+
+/*
+ * If the candidate string is a closer match than the current one saved (or
+ * there is no match saved), save it as the closest match.
+ *
+ * If the source or candidate string is NULL, empty, or too long, this function
+ * takes no action.  Likewise, if the Levenshtein distance exceeds the maximum
+ * allowed or more than half the characters are different, no action is taken.
+ */
+void
+updateClosestMatch(ClosestMatchState *state, const char *candidate)
+{
+	int			dist;
+
+	Assert(state);
+
+	if (state->source == NULL || state->source[0] == '\0' ||
+		candidate == NULL || candidate[0] == '\0')
+		return;
+
+	/*
+	 * To avoid ERROR-ing, we check the lengths here instead of setting
+	 * 'trusted' to false in the call to varstr_levenshtein_less_equal().
+	 */
+	if (strlen(state->source) > MAX_LEVENSHTEIN_STRLEN ||
+		strlen(candidate) > MAX_LEVENSHTEIN_STRLEN)
+		return;
+
+	dist = varstr_levenshtein_less_equal(state->source, strlen(state->source),
+										 candidate, strlen(candidate), 1, 1, 1,
+										 state->max_d, true);
+	if (dist <= state->max_d &&
+		dist <= strlen(state->source) / 2 &&
+		(state->min_d == -1 || dist < state->min_d))
+	{
+		state->min_d = dist;
+		state->match = candidate;
+	}
+}
+
+/*
+ * Return the closest match.  If no suitable candidates were provided via
+ * updateClosestMatch(), return NULL.
+ */
+const char *
+getClosestMatch(ClosestMatchState *state)
+{
+	Assert(state);
+
+	return state->match;
+}
+
+
 /*
  * Unicode support
  */
diff --git a/src/include/utils/varlena.h b/src/include/utils/varlena.h
index c45208a204..2bc3b6e519 100644
--- a/src/include/utils/varlena.h
+++ b/src/include/utils/varlena.h
@@ -38,4 +38,16 @@ extern text *replace_text_regexp(text *src_text, text *pattern_text,
 								 int cflags, Oid collation,
 								 int search_start, int n);
 
+typedef struct ClosestMatchState
+{
+	const char *source;
+	int min_d;
+	int max_d;
+	const char *match;
+} ClosestMatchState;
+
+extern void initClosestMatch(ClosestMatchState *state, const char *source, int max_d);
+extern void updateClosestMatch(ClosestMatchState *state, const char *candidate);
+extern const char *getClosestMatch(ClosestMatchState *state);
+
 #endif
diff --git a/src/test/regress/expected/foreign_data.out b/src/test/regress/expected/foreign_data.out
index 33505352cc..97a0b9cda1 100644
--- a/src/test/regress/expected/foreign_data.out
+++ b/src/test/regress/expected/foreign_data.out
@@ -329,7 +329,6 @@ CREATE SERVER s6 VERSION '16.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbna
 CREATE SERVER s7 TYPE 'oracle' VERSION '17.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbname 'b');
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (foo '1'); -- ERROR
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (host 'localhost', dbname 's8db');
 \des+
                                                              List of foreign servers
@@ -440,7 +439,6 @@ ERROR:  permission denied for foreign-data wrapper foo
 RESET ROLE;
 ALTER SERVER s8 OPTIONS (foo '1');                          -- ERROR option validation
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
 ALTER SERVER s8 OPTIONS (connect_timeout '30', SET dbname 'db1', DROP host);
 SET ROLE regress_test_role;
 ALTER SERVER s1 OWNER TO regress_test_indirect;             -- ERROR
@@ -597,7 +595,7 @@ ERROR:  user mapping for "regress_foreign_data_user" already exists for server "
 CREATE USER MAPPING FOR public SERVER s4 OPTIONS ("this mapping" 'is public');
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (username 'test', password 'secret');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Did you mean "user"?
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (user 'test', password 'secret');
 ALTER SERVER s5 OWNER TO regress_test_role;
 ALTER SERVER s6 OWNER TO regress_test_indirect;
@@ -636,7 +634,7 @@ ALTER USER MAPPING FOR public SERVER s5 OPTIONS (gotcha 'true');            -- E
 ERROR:  user mapping for "public" does not exist for server "s5"
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (username 'test');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Did you mean "user"?
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (DROP user, SET password 'public');
 SET ROLE regress_test_role;
 ALTER USER MAPPING FOR current_user SERVER s5 OPTIONS (ADD modified '1');
-- 
2.25.1

From f9e5d136214e2b55c0bcf0b7b8ec2485aab0e7ba Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathandbossart@gmail.com>
Date: Fri, 2 Sep 2022 14:03:26 -0700
Subject: [PATCH v4 1/1] Adjust assorted hint messages that list all valid
 options.

Instead of listing all valid options, we now try to provide one
that looks similar.  Since this may be useful elsewhere, this
change introduces a new set of functions that can be reused for
similar purposes.
---
 contrib/dblink/dblink.c                       | 27 +++---
 contrib/dblink/expected/dblink.out            |  1 -
 contrib/file_fdw/expected/file_fdw.out        |  2 -
 contrib/file_fdw/file_fdw.c                   | 24 ++++--
 .../postgres_fdw/expected/postgres_fdw.out    |  3 +-
 contrib/postgres_fdw/option.c                 | 23 ++++--
 src/backend/foreign/foreign.c                 | 26 ++++--
 src/backend/utils/adt/varlena.c               | 82 +++++++++++++++++++
 src/include/utils/varlena.h                   | 12 +++
 src/test/regress/expected/foreign_data.out    |  6 +-
 10 files changed, 159 insertions(+), 47 deletions(-)

diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c
index 3df3f9bbe9..8c26adb56c 100644
--- a/contrib/dblink/dblink.c
+++ b/contrib/dblink/dblink.c
@@ -2008,27 +2008,32 @@ dblink_fdw_validator(PG_FUNCTION_ARGS)
 		{
 			/*
 			 * Unknown option, or invalid option for the context specified, so
-			 * complain about it.  Provide a hint with list of valid options
-			 * for the context.
+			 * complain about it.  Provide a hint with a valid option that
+			 * looks similar, if there is one.
 			 */
-			StringInfoData buf;
 			const PQconninfoOption *opt;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 4);
 			for (opt = options; opt->keyword; opt++)
 			{
 				if (is_valid_dblink_option(options, opt->keyword, context))
-					appendStringInfo(&buf, "%s%s",
-									 (buf.len > 0) ? ", " : "",
-									 opt->keyword);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->keyword);
+				}
 			}
+
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_OPTION_NAME_NOT_FOUND),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Perhaps you meant to reference the option \"%s\".",
+							 closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 		}
 	}
 
diff --git a/contrib/dblink/expected/dblink.out b/contrib/dblink/expected/dblink.out
index c7bde6ad07..14d015e4d5 100644
--- a/contrib/dblink/expected/dblink.out
+++ b/contrib/dblink/expected/dblink.out
@@ -897,7 +897,6 @@ $d$;
 CREATE USER MAPPING FOR public SERVER fdtest
   OPTIONS (server 'localhost');  -- fail, can't specify server here
 ERROR:  invalid option "server"
-HINT:  Valid options in this context are: user, password, sslpassword
 CREATE USER MAPPING FOR public SERVER fdtest OPTIONS (user :'USER');
 GRANT USAGE ON FOREIGN SERVER fdtest TO regress_dblink_user;
 GRANT EXECUTE ON FUNCTION dblink_connect_u(text, text) TO regress_dblink_user;
diff --git a/contrib/file_fdw/expected/file_fdw.out b/contrib/file_fdw/expected/file_fdw.out
index 261af1a8b5..36d76ba26c 100644
--- a/contrib/file_fdw/expected/file_fdw.out
+++ b/contrib/file_fdw/expected/file_fdw.out
@@ -166,7 +166,6 @@ ERROR:  invalid option "force_not_null"
 HINT:  There are no valid options in this context.
 CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (force_not_null '*'); -- ERROR
 ERROR:  invalid option "force_not_null"
-HINT:  Valid options in this context are: filename, program, format, header, delimiter, quote, escape, null, encoding
 -- force_null is not allowed to be specified at any foreign object level:
 ALTER FOREIGN DATA WRAPPER file_fdw OPTIONS (ADD force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
@@ -179,7 +178,6 @@ ERROR:  invalid option "force_null"
 HINT:  There are no valid options in this context.
 CREATE FOREIGN TABLE tbl () SERVER file_server OPTIONS (force_null '*'); -- ERROR
 ERROR:  invalid option "force_null"
-HINT:  Valid options in this context are: filename, program, format, header, delimiter, quote, escape, null, encoding
 -- basic query tests
 SELECT * FROM agg_text WHERE b > 10.0 ORDER BY a;
   a  |   b    
diff --git a/contrib/file_fdw/file_fdw.c b/contrib/file_fdw/file_fdw.c
index 4773cadec0..306d349656 100644
--- a/contrib/file_fdw/file_fdw.c
+++ b/contrib/file_fdw/file_fdw.c
@@ -37,6 +37,7 @@
 #include "utils/memutils.h"
 #include "utils/rel.h"
 #include "utils/sampling.h"
+#include "utils/varlena.h"
 
 PG_MODULE_MAGIC;
 
@@ -214,27 +215,32 @@ file_fdw_validator(PG_FUNCTION_ARGS)
 		if (!is_valid_option(def->defname, catalog))
 		{
 			const struct FileFdwOption *opt;
-			StringInfoData buf;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
 			/*
 			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
+			 * with a valid option that looks similar, if there is one.
 			 */
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 4);
 			for (opt = valid_options; opt->optname; opt++)
 			{
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->optname);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->optname);
+				}
 			}
 
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Perhaps you meant to reference the option \"%s\".",
+							 closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 		}
 
 		/*
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 7bf35602b0..ddc185b7d0 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -188,7 +188,6 @@ ALTER USER MAPPING FOR public SERVER testserver1
 ALTER USER MAPPING FOR public SERVER testserver1
 	OPTIONS (ADD sslmode 'require');
 ERROR:  invalid option "sslmode"
-HINT:  Valid options in this context are: user, password, sslpassword, password_required, sslcert, sslkey
 -- But we can add valid ones fine
 ALTER USER MAPPING FOR public SERVER testserver1
 	OPTIONS (ADD sslpassword 'dummy');
@@ -9627,7 +9626,7 @@ DO $d$
     END;
 $d$;
 ERROR:  invalid option "password"
-HINT:  Valid options in this context are: service, passfile, channel_binding, connect_timeout, dbname, host, hostaddr, port, options, application_name, keepalives, keepalives_idle, keepalives_interval, keepalives_count, tcp_user_timeout, sslmode, sslcompression, sslcert, sslkey, sslrootcert, sslcrl, sslcrldir, sslsni, requirepeer, ssl_min_protocol_version, ssl_max_protocol_version, gssencmode, krbsrvname, gsslib, target_session_attrs, use_remote_estimate, fdw_startup_cost, fdw_tuple_cost, extensions, updatable, truncatable, fetch_size, batch_size, async_capable, parallel_commit, keep_connections
+HINT:  Perhaps you meant to reference the option "passfile".
 CONTEXT:  SQL statement "ALTER SERVER loopback_nopw OPTIONS (ADD password 'dummypw')"
 PL/pgSQL function inline_code_block line 3 at EXECUTE
 -- If we add a password for our user mapping instead, we should get a different
diff --git a/contrib/postgres_fdw/option.c b/contrib/postgres_fdw/option.c
index 95dde056eb..b1a14d204b 100644
--- a/contrib/postgres_fdw/option.c
+++ b/contrib/postgres_fdw/option.c
@@ -90,26 +90,31 @@ postgres_fdw_validator(PG_FUNCTION_ARGS)
 		{
 			/*
 			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
+			 * with a valid option that looks similar, if there is one.
 			 */
 			PgFdwOption *opt;
-			StringInfoData buf;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 4);
 			for (opt = postgres_fdw_options; opt->keyword; opt++)
 			{
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->keyword);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->keyword);
+				}
 			}
 
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_FDW_INVALID_OPTION_NAME),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Perhaps you meant to reference the option \"%s\".",
+							 closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 		}
 
 		/*
diff --git a/src/backend/foreign/foreign.c b/src/backend/foreign/foreign.c
index cf222fc3e9..4ef4a765f4 100644
--- a/src/backend/foreign/foreign.c
+++ b/src/backend/foreign/foreign.c
@@ -27,6 +27,7 @@
 #include "utils/memutils.h"
 #include "utils/rel.h"
 #include "utils/syscache.h"
+#include "utils/varlena.h"
 
 
 /*
@@ -621,25 +622,32 @@ postgresql_fdw_validator(PG_FUNCTION_ARGS)
 		if (!is_conninfo_option(def->defname, catalog))
 		{
 			const struct ConnectionOption *opt;
-			StringInfoData buf;
+			const char *closest_match;
+			ClosestMatchState match_state;
+			bool		has_valid_options = false;
 
 			/*
 			 * Unknown option specified, complain about it. Provide a hint
-			 * with list of valid options for the object.
+			 * with a valid option that looks similar, if there is one.
 			 */
-			initStringInfo(&buf);
+			initClosestMatch(&match_state, def->defname, 4);
 			for (opt = libpq_conninfo_options; opt->optname; opt++)
+			{
 				if (catalog == opt->optcontext)
-					appendStringInfo(&buf, "%s%s", (buf.len > 0) ? ", " : "",
-									 opt->optname);
+				{
+					has_valid_options = true;
+					updateClosestMatch(&match_state, opt->optname);
+				}
+			}
 
+			closest_match = getClosestMatch(&match_state);
 			ereport(ERROR,
 					(errcode(ERRCODE_SYNTAX_ERROR),
 					 errmsg("invalid option \"%s\"", def->defname),
-					 buf.len > 0
-					 ? errhint("Valid options in this context are: %s",
-							   buf.data)
-					 : errhint("There are no valid options in this context.")));
+					 has_valid_options ? closest_match ?
+					 errhint("Perhaps you meant to reference the option \"%s\".",
+							 closest_match) : 0 :
+					 errhint("There are no valid options in this context.")));
 
 			PG_RETURN_BOOL(false);
 		}
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index 816c66b7e7..1f6e090821 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -6197,6 +6197,88 @@ rest_of_char_same(const char *s1, const char *s2, int len)
 #include "levenshtein.c"
 
 
+/*
+ * The following *ClosestMatch() functions can be used to determine whether a
+ * user-provided string resembles any known valid values, which is useful for
+ * providing hints in log messages, among other things.  Use these functions
+ * like so:
+ *
+ *		initClosestMatch(&state, source_string, max_distance);
+ *
+ *		for (int i = 0; i < num_valid_strings; i++)
+ *			updateClosestMatch(&state, valid_strings[i]);
+ *
+ *		closestMatch = getClosestMatch(&state);
+ */
+
+/*
+ * Initialize the given state with the source string and maximum Levenshtein
+ * distance to consider.
+ */
+void
+initClosestMatch(ClosestMatchState *state, const char *source, int max_d)
+{
+	Assert(state);
+	Assert(max_d >= 0);
+
+	state->source = source;
+	state->min_d = -1;
+	state->max_d = max_d;
+	state->match = NULL;
+}
+
+/*
+ * If the candidate string is a closer match than the current one saved (or
+ * there is no match saved), save it as the closest match.
+ *
+ * If the source or candidate string is NULL, empty, or too long, this function
+ * takes no action.  Likewise, if the Levenshtein distance exceeds the maximum
+ * allowed or more than half the characters are different, no action is taken.
+ */
+void
+updateClosestMatch(ClosestMatchState *state, const char *candidate)
+{
+	int			dist;
+
+	Assert(state);
+
+	if (state->source == NULL || state->source[0] == '\0' ||
+		candidate == NULL || candidate[0] == '\0')
+		return;
+
+	/*
+	 * To avoid ERROR-ing, we check the lengths here instead of setting
+	 * 'trusted' to false in the call to varstr_levenshtein_less_equal().
+	 */
+	if (strlen(state->source) > MAX_LEVENSHTEIN_STRLEN ||
+		strlen(candidate) > MAX_LEVENSHTEIN_STRLEN)
+		return;
+
+	dist = varstr_levenshtein_less_equal(state->source, strlen(state->source),
+										 candidate, strlen(candidate), 1, 1, 1,
+										 state->max_d, true);
+	if (dist <= state->max_d &&
+		dist <= strlen(state->source) / 2 &&
+		(state->min_d == -1 || dist < state->min_d))
+	{
+		state->min_d = dist;
+		state->match = candidate;
+	}
+}
+
+/*
+ * Return the closest match.  If no suitable candidates were provided via
+ * updateClosestMatch(), return NULL.
+ */
+const char *
+getClosestMatch(ClosestMatchState *state)
+{
+	Assert(state);
+
+	return state->match;
+}
+
+
 /*
  * Unicode support
  */
diff --git a/src/include/utils/varlena.h b/src/include/utils/varlena.h
index c45208a204..2bc3b6e519 100644
--- a/src/include/utils/varlena.h
+++ b/src/include/utils/varlena.h
@@ -38,4 +38,16 @@ extern text *replace_text_regexp(text *src_text, text *pattern_text,
 								 int cflags, Oid collation,
 								 int search_start, int n);
 
+typedef struct ClosestMatchState
+{
+	const char *source;
+	int min_d;
+	int max_d;
+	const char *match;
+} ClosestMatchState;
+
+extern void initClosestMatch(ClosestMatchState *state, const char *source, int max_d);
+extern void updateClosestMatch(ClosestMatchState *state, const char *candidate);
+extern const char *getClosestMatch(ClosestMatchState *state);
+
 #endif
diff --git a/src/test/regress/expected/foreign_data.out b/src/test/regress/expected/foreign_data.out
index 33505352cc..1b4c19a49b 100644
--- a/src/test/regress/expected/foreign_data.out
+++ b/src/test/regress/expected/foreign_data.out
@@ -329,7 +329,6 @@ CREATE SERVER s6 VERSION '16.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbna
 CREATE SERVER s7 TYPE 'oracle' VERSION '17.0' FOREIGN DATA WRAPPER foo OPTIONS (host 'a', dbname 'b');
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (foo '1'); -- ERROR
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
 CREATE SERVER s8 FOREIGN DATA WRAPPER postgresql OPTIONS (host 'localhost', dbname 's8db');
 \des+
                                                              List of foreign servers
@@ -440,7 +439,6 @@ ERROR:  permission denied for foreign-data wrapper foo
 RESET ROLE;
 ALTER SERVER s8 OPTIONS (foo '1');                          -- ERROR option validation
 ERROR:  invalid option "foo"
-HINT:  Valid options in this context are: authtype, service, connect_timeout, dbname, host, hostaddr, port, tty, options, requiressl, sslmode, gsslib
 ALTER SERVER s8 OPTIONS (connect_timeout '30', SET dbname 'db1', DROP host);
 SET ROLE regress_test_role;
 ALTER SERVER s1 OWNER TO regress_test_indirect;             -- ERROR
@@ -597,7 +595,7 @@ ERROR:  user mapping for "regress_foreign_data_user" already exists for server "
 CREATE USER MAPPING FOR public SERVER s4 OPTIONS ("this mapping" 'is public');
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (username 'test', password 'secret');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Perhaps you meant to reference the option "user".
 CREATE USER MAPPING FOR user SERVER s8 OPTIONS (user 'test', password 'secret');
 ALTER SERVER s5 OWNER TO regress_test_role;
 ALTER SERVER s6 OWNER TO regress_test_indirect;
@@ -636,7 +634,7 @@ ALTER USER MAPPING FOR public SERVER s5 OPTIONS (gotcha 'true');            -- E
 ERROR:  user mapping for "public" does not exist for server "s5"
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (username 'test');    -- ERROR
 ERROR:  invalid option "username"
-HINT:  Valid options in this context are: user, password
+HINT:  Perhaps you meant to reference the option "user".
 ALTER USER MAPPING FOR current_user SERVER s8 OPTIONS (DROP user, SET password 'public');
 SET ROLE regress_test_role;
 ALTER USER MAPPING FOR current_user SERVER s5 OPTIONS (ADD modified '1');
-- 
2.25.1