Proposal: variant of regclass

diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
index c24a2c1..d3532d7 100644
--- a/src/backend/utils/adt/regproc.c
+++ b/src/backend/utils/adt/regproc.c
@@ -45,6 +45,8 @@ static char *format_operator_internal(Oid operator_oid, bool force_qualify);
 static char *format_procedure_internal(Oid procedure_oid, bool force_qualify);
 static void parseNameAndArgTypes(const char *string, bool allowNone,
 					 List **names, int *nargs, Oid *argtypes);
+static Datum regclass_gut(char *class_name_or_oid, bool raiseError);
+static List *stringToQualifiedNameList_gut(const char *string, bool raiseError);
 
 
 /*****************************************************************************
@@ -804,21 +806,55 @@ Datum
 regclassin(PG_FUNCTION_ARGS)
 {
 	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
+	Oid			result;
+
+	result = regclass_gut(class_name_or_oid, true);
+	PG_RETURN_OID(result);
+}
+
+Datum
+toregclass(PG_FUNCTION_ARGS)
+{
+	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
+	Oid			result;
+
+	result = regclass_gut(class_name_or_oid, false);
+	PG_RETURN_OID(result);
+}
+
+/*
+ * Gut of regclassin and toregclass.
+ * If raiseError is false, returns InvalidOid upon error.
+ */
+static Datum regclass_gut(char *class_name_or_oid, bool raiseError)
+{
 	Oid			result = InvalidOid;
 	List	   *names;
 
 	/* '-' ? */
 	if (strcmp(class_name_or_oid, "-") == 0)
-		PG_RETURN_OID(InvalidOid);
+		return result;
 
 	/* Numeric OID? */
 	if (class_name_or_oid[0] >= '0' &&
 		class_name_or_oid[0] <= '9' &&
 		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
 	{
-		result = DatumGetObjectId(DirectFunctionCall1(oidin,
-										CStringGetDatum(class_name_or_oid)));
-		PG_RETURN_OID(result);
+		PG_TRY();
+		{
+			result = DatumGetObjectId(DirectFunctionCall1(oidin,
+														  CStringGetDatum(class_name_or_oid)));
+		}
+		PG_CATCH();
+		{
+			if (raiseError)
+				PG_RE_THROW();
+			else
+				return InvalidOid;
+		}
+		PG_END_TRY();
+
+		return result;
 	}
 
 	/* Else it's a name, possibly schema-qualified */
@@ -848,28 +884,36 @@ regclassin(PG_FUNCTION_ARGS)
 		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
 			result = HeapTupleGetOid(tuple);
 		else
-			ereport(ERROR,
-					(errcode(ERRCODE_UNDEFINED_TABLE),
-			   errmsg("relation \"%s\" does not exist", class_name_or_oid)));
+			if (raiseError)
+				ereport(ERROR,
+						(errcode(ERRCODE_UNDEFINED_TABLE),
+						 errmsg("relation \"%s\" does not exist", class_name_or_oid)));
+			else
+				return InvalidOid;
 
 		/* We assume there can be only one match */
 
 		systable_endscan(sysscan);
 		heap_close(hdesc, AccessShareLock);
 
-		PG_RETURN_OID(result);
+		return result;
 	}
 
 	/*
 	 * Normal case: parse the name into components and see if it matches any
 	 * pg_class entries in the current search path.
 	 */
-	names = stringToQualifiedNameList(class_name_or_oid);
+	names = stringToQualifiedNameList_gut(class_name_or_oid, false);
+	if (names == NIL)
+		return InvalidOid;
 
 	/* We might not even have permissions on this relation; don't lock it. */
-	result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, false);
+	if (raiseError)
+		result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, false);
+	else
+		result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, true);
 
-	PG_RETURN_OID(result);
+	return result;
 }
 
 /*
@@ -1352,6 +1396,12 @@ text_regclass(PG_FUNCTION_ARGS)
 List *
 stringToQualifiedNameList(const char *string)
 {
+	return stringToQualifiedNameList_gut(string, true);
+}
+
+static List *
+stringToQualifiedNameList_gut(const char *string, bool raiseError)
+{
 	char	   *rawname;
 	List	   *result = NIL;
 	List	   *namelist;
@@ -1361,14 +1411,30 @@ stringToQualifiedNameList(const char *string)
 	rawname = pstrdup(string);
 
 	if (!SplitIdentifierString(rawname, '.', &namelist))
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_NAME),
-				 errmsg("invalid name syntax")));
+	{
+		if (raiseError)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_NAME),
+					 errmsg("invalid name syntax")));
+		else
+		{
+			pfree(rawname);
+			return result;
+		}
+	}
 
 	if (namelist == NIL)
-		ereport(ERROR,
-				(errcode(ERRCODE_INVALID_NAME),
-				 errmsg("invalid name syntax")));
+	{
+		if (raiseError)
+			ereport(ERROR,
+					(errcode(ERRCODE_INVALID_NAME),
+					 errmsg("invalid name syntax")));
+		else
+		{
+			pfree(rawname);
+			return result;
+		}
+	}
 
 	foreach(l, namelist)
 	{
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 0117500..3f00b05 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -3304,6 +3304,7 @@ DATA(insert OID = 2218 (  regclassin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2
 DESCR("I/O");
 DATA(insert OID = 2219 (  regclassout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2205" _null_ _null_ _null_ _null_ regclassout _null_ _null_ _null_ ));
 DESCR("I/O");
+DATA(insert OID = 3179 (  toregclass		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "2275" _null_ _null_ _null_ _null_ toregclass _null_ _null_ _null_ ));
 DATA(insert OID = 2220 (  regtypein			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ regtypein _null_ _null_ _null_ ));
 DESCR("I/O");
 DATA(insert OID = 2221 (  regtypeout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2206" _null_ _null_ _null_ _null_ regtypeout _null_ _null_ _null_ ));
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index 1bfd145..1b57a7b 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -600,6 +600,7 @@ extern Datum regclassin(PG_FUNCTION_ARGS);
 extern Datum regclassout(PG_FUNCTION_ARGS);
 extern Datum regclassrecv(PG_FUNCTION_ARGS);
 extern Datum regclasssend(PG_FUNCTION_ARGS);
+extern Datum toregclass(PG_FUNCTION_ARGS);
 extern Datum regtypein(PG_FUNCTION_ARGS);
 extern Datum regtypeout(PG_FUNCTION_ARGS);
 extern Datum regtyperecv(PG_FUNCTION_ARGS);

diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
index c24a2c1..0406c30 100644
--- a/src/backend/utils/adt/regproc.c
+++ b/src/backend/utils/adt/regproc.c
@@ -45,6 +45,7 @@ static char *format_operator_internal(Oid operator_oid, bool force_qualify);
 static char *format_procedure_internal(Oid procedure_oid, bool force_qualify);
 static void parseNameAndArgTypes(const char *string, bool allowNone,
 					 List **names, int *nargs, Oid *argtypes);
+static Datum regclass_guts(char *class_name_or_oid, bool raiseError);
 
 
 /*****************************************************************************
@@ -804,21 +805,50 @@ Datum
 regclassin(PG_FUNCTION_ARGS)
 {
 	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
+	Oid			result;
+
+	result = regclass_guts(class_name_or_oid, true);
+	PG_RETURN_OID(result);
+}
+
+/*
+ * toregclass		- converts "classname" to class OID
+ *
+ * Diffrence from rgclassin is, this does not throw an error if the classname
+ * does not exist.
+ * Note: this is not an I/O function.
+ */
+Datum
+toregclass(PG_FUNCTION_ARGS)
+{
+	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
+	Oid			result;
+
+	result = regclass_guts(class_name_or_oid, false);
+	PG_RETURN_OID(result);
+}
+
+/*
+ * Guts of regclassin and toregclass.
+ * If raiseError is false, returns InvalidOid upon error.
+ */
+static Datum regclass_guts(char *class_name_or_oid, bool raiseError)
+{
 	Oid			result = InvalidOid;
 	List	   *names;
 
 	/* '-' ? */
 	if (strcmp(class_name_or_oid, "-") == 0)
-		PG_RETURN_OID(InvalidOid);
+		return result;
 
 	/* Numeric OID? */
 	if (class_name_or_oid[0] >= '0' &&
 		class_name_or_oid[0] <= '9' &&
 		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
 	{
-		result = DatumGetObjectId(DirectFunctionCall1(oidin,
+ 		result = DatumGetObjectId(DirectFunctionCall1(oidin,
 										CStringGetDatum(class_name_or_oid)));
-		PG_RETURN_OID(result);
+		return result;
 	}
 
 	/* Else it's a name, possibly schema-qualified */
@@ -848,16 +878,19 @@ regclassin(PG_FUNCTION_ARGS)
 		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
 			result = HeapTupleGetOid(tuple);
 		else
-			ereport(ERROR,
-					(errcode(ERRCODE_UNDEFINED_TABLE),
-			   errmsg("relation \"%s\" does not exist", class_name_or_oid)));
+			if (raiseError)
+				ereport(ERROR,
+						(errcode(ERRCODE_UNDEFINED_TABLE),
+						 errmsg("relation \"%s\" does not exist", class_name_or_oid)));
+			else
+				return InvalidOid;
 
 		/* We assume there can be only one match */
 
 		systable_endscan(sysscan);
 		heap_close(hdesc, AccessShareLock);
 
-		PG_RETURN_OID(result);
+		return result;
 	}
 
 	/*
@@ -865,11 +898,16 @@ regclassin(PG_FUNCTION_ARGS)
 	 * pg_class entries in the current search path.
 	 */
 	names = stringToQualifiedNameList(class_name_or_oid);
+	if (names == NIL)
+		return InvalidOid;
 
 	/* We might not even have permissions on this relation; don't lock it. */
-	result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, false);
+	if (raiseError)
+		result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, false);
+	else
+		result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, true);
 
-	PG_RETURN_OID(result);
+	return result;
 }
 
 /*
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 0117500..472ccad 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -3304,13 +3304,14 @@ DATA(insert OID = 2218 (  regclassin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2
 DESCR("I/O");
 DATA(insert OID = 2219 (  regclassout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2205" _null_ _null_ _null_ _null_ regclassout _null_ _null_ _null_ ));
 DESCR("I/O");
+DATA(insert OID = 3179 (  toregclass		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "2275" _null_ _null_ _null_ _null_ toregclass _null_ _null_ _null_ ));
+DESCR("convert classname to regclass");
 DATA(insert OID = 2220 (  regtypein			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ regtypein _null_ _null_ _null_ ));
 DESCR("I/O");
 DATA(insert OID = 2221 (  regtypeout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2206" _null_ _null_ _null_ _null_ regtypeout _null_ _null_ _null_ ));
 DESCR("I/O");
 DATA(insert OID = 1079 (  regclass			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "25" _null_ _null_ _null_ _null_	text_regclass _null_ _null_ _null_ ));
 DESCR("convert text to regclass");
-
 DATA(insert OID = 2246 ( fmgr_internal_validator PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2278 "26" _null_ _null_ _null_ _null_ fmgr_internal_validator _null_ _null_ _null_ ));
 DESCR("(internal)");
 DATA(insert OID = 2247 ( fmgr_c_validator	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2278 "26" _null_ _null_ _null_ _null_ fmgr_c_validator _null_ _null_ _null_ ));
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index 1bfd145..1b57a7b 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -600,6 +600,7 @@ extern Datum regclassin(PG_FUNCTION_ARGS);
 extern Datum regclassout(PG_FUNCTION_ARGS);
 extern Datum regclassrecv(PG_FUNCTION_ARGS);
 extern Datum regclasssend(PG_FUNCTION_ARGS);
+extern Datum toregclass(PG_FUNCTION_ARGS);
 extern Datum regtypein(PG_FUNCTION_ARGS);
 extern Datum regtypeout(PG_FUNCTION_ARGS);
 extern Datum regtyperecv(PG_FUNCTION_ARGS);

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
new file mode 100644
index c76d357..61daf55
*** a/doc/src/sgml/func.sgml
--- b/doc/src/sgml/func.sgml
*************** SELECT pg_type_is_visible('myschema.widg
*** 14831,14836 ****
--- 14831,14852 ----
      <primary>collation for</primary>
     </indexterm>
  
+    <indexterm>
+     <primary>to_regclass</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regproc</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regoper</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regtype</primary>
+    </indexterm>
+ 
    <para>
     <xref linkend="functions-info-catalog-table"> lists functions that
     extract information from the system catalogs.
*************** SELECT pg_type_is_visible('myschema.widg
*** 15001,15006 ****
--- 15017,15042 ----
         <entry><type>text</type></entry>
         <entry>get the collation of the argument</entry>
        </row>
+       <row>
+        <entry><literal><function>to_regclass(<parameter>table_name</parameter>)</function></literal></entry>
+        <entry><type>regclass</type></entry>
+        <entry>get the table oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regproc(<parameter>func_name</parameter>)</function></literal></entry>
+        <entry><type>regproc</type></entry>
+        <entry>get the function oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regoper(<parameter>operator_name</parameter>)</function></literal></entry>
+        <entry><type>regoper</type></entry>
+        <entry>get the operator oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regtype(<parameter>type_name</parameter>)</function></literal></entry>
+        <entry><type>regtype</type></entry>
+        <entry>get the type oid</entry>
+       </row>
       </tbody>
      </tgroup>
     </table>
*************** SELECT collation for ('foo' COLLATE "de_
*** 15166,15171 ****
--- 15202,15213 ----
    is not of a collatable data type, then an error is raised.
    </para>
  
+   <para>
+     to_regclass, to_regproc, to_regoper and to_regtype are similar to
+     regclass, regproc, regoper and regtype except that if the requested object
+     is not found, returns InvalidOid, rather than raises an error.
+   </para>
+ 
     <indexterm>
      <primary>col_description</primary>
     </indexterm>
diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
new file mode 100644
index 635aa1d..0612e53
*** a/src/backend/parser/parse_type.c
--- b/src/backend/parser/parse_type.c
***************
*** 30,35 ****
--- 30,38 ----
  
  static int32 typenameTypeMod(ParseState *pstate, const TypeName *typeName,
  				Type typ);
+ static void typenameTypeIdAndMod_guts(ParseState *pstate, const TypeName *typeName,
+ 				Oid *typeid_p, int32 *typmod_p, bool missing_ok);
+ static void parseTypeString_guts(const char *str, Oid *typeid_p, int32 *typmod_p, bool missing_ok);
  
  
  /*
*************** void
*** 241,251 ****
  typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName,
  					 Oid *typeid_p, int32 *typmod_p)
  {
  	Type		tup;
  
! 	tup = typenameType(pstate, typeName, typmod_p);
! 	*typeid_p = HeapTupleGetOid(tup);
! 	ReleaseSysCache(tup);
  }
  
  /*
--- 244,293 ----
  typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName,
  					 Oid *typeid_p, int32 *typmod_p)
  {
+ 	typenameTypeIdAndMod_guts(pstate, typeName, typeid_p, typmod_p, false);
+ }
+ 
+ /*
+  * typenameTypeIdAndModMissingOk - given a TypeName, return the type's OID and typmod
+  *
+  * Diffrence from typenameTypeIdMod is, this does not throw an error if the typeName
+  * does not exist.
+  */
+ void
+ typenameTypeIdAndModMissingOk(ParseState *pstate, const TypeName *typeName,
+ 					 Oid *typeid_p, int32 *typmod_p)
+ {
+ 	typenameTypeIdAndMod_guts(pstate, typeName, typeid_p, typmod_p, true);
+ }
+ 
+ /*
+  * Guts of typenameTypeIdAndMod and typenameTypeIdAndModMissingOk.
+  * If missing_ok is true, returns InvalidOid upon error.
+  */
+ static void
+ typenameTypeIdAndMod_guts(ParseState *pstate, const TypeName *typeName,
+ 					 Oid *typeid_p, int32 *typmod_p,
+ 					 bool missing_ok)
+ {
  	Type		tup;
  
! 	if (missing_ok)
! 	{
! 		tup = LookupTypeName(pstate, typeName, typmod_p);
! 		if (tup == NULL || !((Form_pg_type) GETSTRUCT(tup))->typisdefined)
! 			*typeid_p = InvalidOid;
! 		else
! 			*typeid_p = HeapTupleGetOid(tup);
! 
! 		if (tup)
! 			ReleaseSysCache(tup);
! 	}
! 	else
! 	{
! 		tup = typenameType(pstate, typeName, typmod_p);
! 		*typeid_p = HeapTupleGetOid(tup);
! 		ReleaseSysCache(tup);
! 	}
  }
  
  /*
*************** pts_error_callback(void *arg)
*** 662,667 ****
--- 704,729 ----
  void
  parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p)
  {
+ 	parseTypeString_guts(str, typeid_p, typmod_p, false);
+ }
+ 
+ /*
+  * This is equivalent to parseTyepString, except that this does not throw an
+  * error if the type does not exist.
+  */
+ void
+ parseTypeStringMissingOk(const char *str, Oid *typeid_p, int32 *typmod_p)
+ {
+ 	parseTypeString_guts(str, typeid_p, typmod_p, true);
+ }
+ 
+ /*
+  * Guts of parseTypeString and parseTypeStringMissingOk.
+  * If missing_ok is true, returns InvalidOid upon error.
+  */
+ static void
+ parseTypeString_guts(const char *str, Oid *typeid_p, int32 *typmod_p, bool missing_ok)
+ {
  	StringInfoData buf;
  	List	   *raw_parsetree_list;
  	SelectStmt *stmt;
*************** parseTypeString(const char *str, Oid *ty
*** 734,740 ****
  	if (typeName->setof)
  		goto fail;
  
! 	typenameTypeIdAndMod(NULL, typeName, typeid_p, typmod_p);
  
  	pfree(buf.data);
  
--- 796,805 ----
  	if (typeName->setof)
  		goto fail;
  
! 	if (missing_ok)
! 		typenameTypeIdAndModMissingOk(NULL, typeName, typeid_p, typmod_p);
! 	else
! 		typenameTypeIdAndMod(NULL, typeName, typeid_p, typmod_p);
  
  	pfree(buf.data);
  
diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
new file mode 100644
index 5023d16..0194187
*** a/src/backend/utils/adt/regproc.c
--- b/src/backend/utils/adt/regproc.c
*************** static char *format_operator_internal(Oi
*** 45,50 ****
--- 45,54 ----
  static char *format_procedure_internal(Oid procedure_oid, bool force_qualify);
  static void parseNameAndArgTypes(const char *string, bool allowNone,
  					 List **names, int *nargs, Oid *argtypes);
+ static Datum regoper_guts(char *opr_name_or_oid, bool raiseError);
+ static Datum regproc_guts(char *pro_name_or_oid, bool raiseError);
+ static Datum regclass_guts(char *class_name_or_oid, bool raiseError);
+ static Datum regtype_guts(char *typ_name_or_oid, bool raiseError);
  
  
  /*****************************************************************************
*************** Datum
*** 63,68 ****
--- 67,98 ----
  regprocin(PG_FUNCTION_ARGS)
  {
  	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regproc_guts(pro_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regproc	- converts "proname" to proc OID
+  *
+  * Diffrence from regprocin is, this does not throw an error if the proname
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regproc(PG_FUNCTION_ARGS)
+ {
+ 	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regproc_guts(pro_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ Datum
+ regproc_guts(char *pro_name_or_oid, bool raiseError)
+ {
  	RegProcedure result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
*************** regprocin(PG_FUNCTION_ARGS)
*** 117,133 ****
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 
  		else if (matches > 1)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one function named \"%s\"",
! 							pro_name_or_oid)));
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 147,172 ----
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 		{
! 			if (raiseError)
! 				ereport(ERROR,
! 						(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 			else
! 				return InvalidOid;
! 		}
  		else if (matches > 1)
! 		{
! 			if (raiseError)
! 				ereport(ERROR,
! 						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 						 errmsg("more than one function named \"%s\"",
! 								pro_name_or_oid)));
! 			else
! 				return InvalidOid;
! 		}
  
! 		return result;
  	}
  
  	/*
*************** regprocin(PG_FUNCTION_ARGS)
*** 138,155 ****
  	clist = FuncnameGetCandidates(names, -1, NIL, false, false);
  
  	if (clist == NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
  	else if (clist->next != NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 				 errmsg("more than one function named \"%s\"",
  						pro_name_or_oid)));
  
  	result = clist->oid;
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 177,204 ----
  	clist = FuncnameGetCandidates(names, -1, NIL, false, false);
  
  	if (clist == NULL)
! 	{
! 		if (raiseError)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 		else
! 			return InvalidOid;
! 	}
  	else if (clist->next != NULL)
! 	{
! 		if (raiseError)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one function named \"%s\"",
  						pro_name_or_oid)));
+ 		else
+ 			return InvalidOid;
+ 	}
  
  	result = clist->oid;
  
! 	return result;
  }
  
  /*
*************** Datum
*** 431,443 ****
  regoperin(PG_FUNCTION_ARGS)
  {
  	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
  	Oid			result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '0' ? */
  	if (strcmp(opr_name_or_oid, "0") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (opr_name_or_oid[0] >= '0' &&
--- 480,521 ----
  regoperin(PG_FUNCTION_ARGS)
  {
  	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regoper_guts(opr_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regoper		- converts "oprname" to operator OID
+  *
+  * Diffrence from regoper is, this does not throw an error if the operator
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regoper(PG_FUNCTION_ARGS)
+ {
+ 	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regoper_guts(opr_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * Guts of regoperin and to_regoper.
+  * If raiseError is false, returns InvalidOid upon error.
+  */
+ static Datum regoper_guts(char *opr_name_or_oid, bool raiseError)
+ {
  	Oid			result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '0' ? */
  	if (strcmp(opr_name_or_oid, "0") == 0)
! 		return InvalidOid;
  
  	/* Numeric OID? */
  	if (opr_name_or_oid[0] >= '0' &&
*************** regoperin(PG_FUNCTION_ARGS)
*** 446,452 ****
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
  										  CStringGetDatum(opr_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a name, possibly schema-qualified */
--- 524,530 ----
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
  										  CStringGetDatum(opr_name_or_oid)));
! 		return result;
  	}
  
  	/* Else it's a name, possibly schema-qualified */
*************** regoperin(PG_FUNCTION_ARGS)
*** 485,500 ****
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("operator does not exist: %s", opr_name_or_oid)));
  		else if (matches > 1)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one operator named %s",
! 							opr_name_or_oid)));
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 563,588 ----
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 		{
! 			if (raiseError)
! 				ereport(ERROR,
! 						(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 						 errmsg("operator does not exist: %s", opr_name_or_oid)));
! 			else
! 				return InvalidOid;
! 		}
  		else if (matches > 1)
! 		{
! 			if (raiseError)
! 				ereport(ERROR,
! 						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 						 errmsg("more than one operator named %s",
! 								opr_name_or_oid)));
! 			else
! 				return InvalidOid;
! 		}
  
! 		return result;
  	}
  
  	/*
*************** regoperin(PG_FUNCTION_ARGS)
*** 505,522 ****
  	clist = OpernameGetCandidates(names, '\0');
  
  	if (clist == NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("operator does not exist: %s", opr_name_or_oid)));
  	else if (clist->next != NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 				 errmsg("more than one operator named %s",
! 						opr_name_or_oid)));
  
  	result = clist->oid;
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 593,620 ----
  	clist = OpernameGetCandidates(names, '\0');
  
  	if (clist == NULL)
! 	{
! 		if (raiseError)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("operator does not exist: %s", opr_name_or_oid)));
! 		else
! 			return InvalidOid;
! 	}
  	else if (clist->next != NULL)
! 	{
! 		if (raiseError)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one operator named %s",
! 							opr_name_or_oid)));
! 		else
! 			return InvalidOid;
! 	}
  
  	result = clist->oid;
  
! 	return result;
  }
  
  /*
*************** Datum
*** 804,815 ****
  regclassin(PG_FUNCTION_ARGS)
  {
  	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
  	Oid			result = InvalidOid;
  	List	   *names;
  
  	/* '-' ? */
  	if (strcmp(class_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (class_name_or_oid[0] >= '0' &&
--- 902,942 ----
  regclassin(PG_FUNCTION_ARGS)
  {
  	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regclass_guts(class_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regclass		- converts "classname" to class OID
+  *
+  * Diffrence from regclassin is, this does not throw an error if the classname
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regclass(PG_FUNCTION_ARGS)
+ {
+ 	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regclass_guts(class_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * Guts of regclassin and to_regclass.
+  * If raiseError is false, returns InvalidOid upon error.
+  */
+ static Datum regclass_guts(char *class_name_or_oid, bool raiseError)
+ {
  	Oid			result = InvalidOid;
  	List	   *names;
  
  	/* '-' ? */
  	if (strcmp(class_name_or_oid, "-") == 0)
! 		return result;
  
  	/* Numeric OID? */
  	if (class_name_or_oid[0] >= '0' &&
*************** regclassin(PG_FUNCTION_ARGS)
*** 818,824 ****
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
  										CStringGetDatum(class_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a name, possibly schema-qualified */
--- 945,951 ----
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
  										CStringGetDatum(class_name_or_oid)));
! 		return result;
  	}
  
  	/* Else it's a name, possibly schema-qualified */
*************** regclassin(PG_FUNCTION_ARGS)
*** 848,863 ****
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
  		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_TABLE),
! 			   errmsg("relation \"%s\" does not exist", class_name_or_oid)));
  
  		/* We assume there can be only one match */
  
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 975,993 ----
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
  		else
! 			if (raiseError)
! 				ereport(ERROR,
! 						(errcode(ERRCODE_UNDEFINED_TABLE),
! 						 errmsg("relation \"%s\" does not exist", class_name_or_oid)));
! 			else
! 				return InvalidOid;
  
  		/* We assume there can be only one match */
  
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		return result;
  	}
  
  	/*
*************** regclassin(PG_FUNCTION_ARGS)
*** 865,875 ****
  	 * pg_class entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(class_name_or_oid);
  
  	/* We might not even have permissions on this relation; don't lock it. */
! 	result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, false);
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 995,1010 ----
  	 * pg_class entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(class_name_or_oid);
+ 	if (names == NIL)
+ 		return InvalidOid;
  
  	/* We might not even have permissions on this relation; don't lock it. */
! 	if (raiseError)
! 		result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, false);
! 	else
! 		result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, true);
  
! 	return result;
  }
  
  /*
*************** Datum
*** 968,973 ****
--- 1103,1137 ----
  regtypein(PG_FUNCTION_ARGS)
  {
  	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regtype_guts(typ_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regtype		- converts "typename" to type OID
+  *
+  * Diffrence from regtypein is, this does not throw an error if the typename
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regtype(PG_FUNCTION_ARGS)
+ {
+ 	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regtype_guts(typ_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * Guts of regtypein and to_regtype.
+  * If raiseError is false, returns InvalidOid upon error.
+  */
+ static Datum regtype_guts(char *typ_name_or_oid, bool raiseError)
+ {
  	Oid			result = InvalidOid;
  	int32		typmod;
  
*************** regtypein(PG_FUNCTION_ARGS)
*** 982,988 ****
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
  										  CStringGetDatum(typ_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a type name, possibly schema-qualified or decorated */
--- 1146,1152 ----
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
  										  CStringGetDatum(typ_name_or_oid)));
! 		return result;
  	}
  
  	/* Else it's a type name, possibly schema-qualified or decorated */
*************** regtypein(PG_FUNCTION_ARGS)
*** 1011,1017 ****
  
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
! 		else
  			ereport(ERROR,
  					(errcode(ERRCODE_UNDEFINED_OBJECT),
  					 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
--- 1175,1181 ----
  
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
! 		else if (raiseError)
  			ereport(ERROR,
  					(errcode(ERRCODE_UNDEFINED_OBJECT),
  					 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
*************** regtypein(PG_FUNCTION_ARGS)
*** 1021,1036 ****
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
  	 * Normal case: invoke the full parser to deal with special cases such as
  	 * array syntax.
  	 */
! 	parseTypeString(typ_name_or_oid, &result, &typmod);
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 1185,1203 ----
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		return result;
  	}
  
  	/*
  	 * Normal case: invoke the full parser to deal with special cases such as
  	 * array syntax.
  	 */
! 	if (raiseError)
! 		parseTypeString(typ_name_or_oid, &result, &typmod);
! 	else
! 		parseTypeStringMissingOk(typ_name_or_oid, &result, &typmod);
  
! 	return result;
  }
  
  /*
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
new file mode 100644
index ab05c46..74f8bf9
*** a/src/include/catalog/pg_proc.h
--- b/src/include/catalog/pg_proc.h
*************** DATA(insert OID =  44 (  regprocin		   P
*** 173,178 ****
--- 173,180 ----
  DESCR("I/O");
  DATA(insert OID =  45 (  regprocout		   PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "24" _null_ _null_ _null_ _null_ regprocout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3196 (  to_regproc		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "2275" _null_ _null_ _null_ _null_ to_regproc _null_ _null_ _null_ ));
+ DESCR("convert proname to regproc");
  DATA(insert OID =  46 (  textin			   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 25 "2275" _null_ _null_ _null_ _null_ textin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID =  47 (  textout		   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2275 "25" _null_ _null_ _null_ _null_ textout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2214 (  regoperin			PG
*** 3296,3301 ****
--- 3298,3305 ----
  DESCR("I/O");
  DATA(insert OID = 2215 (  regoperout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2203" _null_ _null_ _null_ _null_ regoperout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3180 (  to_regoper		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2203 "2275" _null_ _null_ _null_ _null_ to_regoper _null_ _null_ _null_ ));
+ DESCR("convert operator name to regoper");
  DATA(insert OID = 2216 (  regoperatorin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2204 "2275" _null_ _null_ _null_ _null_ regoperatorin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2217 (  regoperatorout	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2204" _null_ _null_ _null_ _null_ regoperatorout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2218 (  regclassin		PG
*** 3304,3313 ****
--- 3308,3321 ----
  DESCR("I/O");
  DATA(insert OID = 2219 (  regclassout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2205" _null_ _null_ _null_ _null_ regclassout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3179 (  to_regclass		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "2275" _null_ _null_ _null_ _null_ to_regclass _null_ _null_ _null_ ));
+ DESCR("convert classname to regclass");
  DATA(insert OID = 2220 (  regtypein			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ regtypein _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2221 (  regtypeout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2206" _null_ _null_ _null_ _null_ regtypeout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3195 (  to_regtype		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ to_regtype _null_ _null_ _null_ ));
+ DESCR("convert type name to regtype");
  DATA(insert OID = 1079 (  regclass			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "25" _null_ _null_ _null_ _null_	text_regclass _null_ _null_ _null_ ));
  DESCR("convert text to regclass");
  
diff --git a/src/include/parser/parse_type.h b/src/include/parser/parse_type.h
new file mode 100644
index 9208bad..470e2a6
*** a/src/include/parser/parse_type.h
--- b/src/include/parser/parse_type.h
*************** extern Type typenameType(ParseState *pst
*** 26,31 ****
--- 26,33 ----
  extern Oid	typenameTypeId(ParseState *pstate, const TypeName *typeName);
  extern void typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName,
  					 Oid *typeid_p, int32 *typmod_p);
+ extern void typenameTypeIdAndModMissingOk(ParseState *pstate, const TypeName *typeName,
+ 					 Oid *typeid_p, int32 *typmod_p);
  
  extern char *TypeNameToString(const TypeName *typeName);
  extern char *TypeNameListToString(List *typenames);
*************** extern Datum stringTypeDatum(Type tp, ch
*** 46,51 ****
--- 48,54 ----
  extern Oid	typeidTypeRelid(Oid type_id);
  
  extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p);
+ extern void parseTypeStringMissingOk(const char *str, Oid *typeid_p, int32 *typmod_p);
  
  #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
  
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
new file mode 100644
index b90d88d..85dee8a
*** a/src/include/utils/builtins.h
--- b/src/include/utils/builtins.h
*************** extern char *regexp_fixed_prefix(text *t
*** 597,602 ****
--- 597,603 ----
  /* regproc.c */
  extern Datum regprocin(PG_FUNCTION_ARGS);
  extern Datum regprocout(PG_FUNCTION_ARGS);
+ extern Datum to_regproc(PG_FUNCTION_ARGS);
  extern Datum regprocrecv(PG_FUNCTION_ARGS);
  extern Datum regprocsend(PG_FUNCTION_ARGS);
  extern Datum regprocedurein(PG_FUNCTION_ARGS);
*************** extern Datum regoperin(PG_FUNCTION_ARGS)
*** 607,612 ****
--- 608,614 ----
  extern Datum regoperout(PG_FUNCTION_ARGS);
  extern Datum regoperrecv(PG_FUNCTION_ARGS);
  extern Datum regopersend(PG_FUNCTION_ARGS);
+ extern Datum to_regoper(PG_FUNCTION_ARGS);
  extern Datum regoperatorin(PG_FUNCTION_ARGS);
  extern Datum regoperatorout(PG_FUNCTION_ARGS);
  extern Datum regoperatorrecv(PG_FUNCTION_ARGS);
*************** extern Datum regclassin(PG_FUNCTION_ARGS
*** 615,624 ****
--- 617,628 ----
  extern Datum regclassout(PG_FUNCTION_ARGS);
  extern Datum regclassrecv(PG_FUNCTION_ARGS);
  extern Datum regclasssend(PG_FUNCTION_ARGS);
+ extern Datum to_regclass(PG_FUNCTION_ARGS);
  extern Datum regtypein(PG_FUNCTION_ARGS);
  extern Datum regtypeout(PG_FUNCTION_ARGS);
  extern Datum regtyperecv(PG_FUNCTION_ARGS);
  extern Datum regtypesend(PG_FUNCTION_ARGS);
+ extern Datum to_regtype(PG_FUNCTION_ARGS);
  extern Datum regconfigin(PG_FUNCTION_ARGS);
  extern Datum regconfigout(PG_FUNCTION_ARGS);
  extern Datum regconfigrecv(PG_FUNCTION_ARGS);

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
new file mode 100644
index c0a75de..1d3867b
*** a/doc/src/sgml/func.sgml
--- b/doc/src/sgml/func.sgml
*************** SELECT pg_type_is_visible('myschema.widg
*** 14854,14859 ****
--- 14854,14875 ----
      <primary>collation for</primary>
     </indexterm>
  
+    <indexterm>
+     <primary>to_regclass</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regproc</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regoper</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regtype</primary>
+    </indexterm>
+ 
    <para>
     <xref linkend="functions-info-catalog-table"> lists functions that
     extract information from the system catalogs.
*************** SELECT pg_type_is_visible('myschema.widg
*** 15024,15029 ****
--- 15040,15065 ----
         <entry><type>text</type></entry>
         <entry>get the collation of the argument</entry>
        </row>
+       <row>
+        <entry><literal><function>to_regclass(<parameter>table_name</parameter>)</function></literal></entry>
+        <entry><type>regclass</type></entry>
+        <entry>get the table oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regproc(<parameter>func_name</parameter>)</function></literal></entry>
+        <entry><type>regproc</type></entry>
+        <entry>get the function oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regoper(<parameter>operator_name</parameter>)</function></literal></entry>
+        <entry><type>regoper</type></entry>
+        <entry>get the operator oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regtype(<parameter>type_name</parameter>)</function></literal></entry>
+        <entry><type>regtype</type></entry>
+        <entry>get the type oid</entry>
+       </row>
       </tbody>
      </tgroup>
     </table>
*************** SELECT collation for ('foo' COLLATE "de_
*** 15189,15194 ****
--- 15225,15236 ----
    is not of a collatable data type, then an error is raised.
    </para>
  
+   <para>
+     to_regclass, to_regproc, to_regoper and to_regtype are similar to
+     regclass, regproc, regoper and regtype except that if the requested object
+     is not found, returns InvalidOid, rather than raises an error.
+   </para>
+ 
     <indexterm>
      <primary>col_description</primary>
     </indexterm>
diff --git a/src/backend/access/common/tupdesc.c b/src/backend/access/common/tupdesc.c
new file mode 100644
index db8cb82..e4aa1eb
*** a/src/backend/access/common/tupdesc.c
--- b/src/backend/access/common/tupdesc.c
*************** BuildDescForRelation(List *schema)
*** 617,623 ****
  		attnum++;
  
  		attname = entry->colname;
! 		typenameTypeIdAndMod(NULL, entry->typeName, &atttypid, &atttypmod);
  
  		aclresult = pg_type_aclcheck(atttypid, GetUserId(), ACL_USAGE);
  		if (aclresult != ACLCHECK_OK)
--- 617,623 ----
  		attnum++;
  
  		attname = entry->colname;
! 		typenameTypeIdAndMod(NULL, entry->typeName, &atttypid, &atttypmod, false);
  
  		aclresult = pg_type_aclcheck(atttypid, GetUserId(), ACL_USAGE);
  		if (aclresult != ACLCHECK_OK)
diff --git a/src/backend/catalog/namespace.c b/src/backend/catalog/namespace.c
new file mode 100644
index 6c2a5d2..0253610
*** a/src/backend/catalog/namespace.c
--- b/src/backend/catalog/namespace.c
*************** OpernameGetOprid(List *names, Oid oprlef
*** 1556,1562 ****
   * will be InvalidOid for a prefix or postfix oprkind.	nargs is 2, too.
   */
  FuncCandidateList
! OpernameGetCandidates(List *names, char oprkind)
  {
  	FuncCandidateList resultList = NULL;
  	char	   *resultSpace = NULL;
--- 1556,1562 ----
   * will be InvalidOid for a prefix or postfix oprkind.	nargs is 2, too.
   */
  FuncCandidateList
! OpernameGetCandidates(List *names, char oprkind, bool missing_ok)
  {
  	FuncCandidateList resultList = NULL;
  	char	   *resultSpace = NULL;
*************** OpernameGetCandidates(List *names, char 
*** 1573,1579 ****
  	if (schemaname)
  	{
  		/* use exact schema given */
! 		namespaceId = LookupExplicitNamespace(schemaname, false);
  	}
  	else
  	{
--- 1573,1581 ----
  	if (schemaname)
  	{
  		/* use exact schema given */
! 		namespaceId = LookupExplicitNamespace(schemaname, missing_ok);
!  		if (!OidIsValid(namespaceId))
!  			return NULL;
  	}
  	else
  	{
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
new file mode 100644
index 08b037e..adc2680
*** a/src/backend/commands/tablecmds.c
--- b/src/backend/commands/tablecmds.c
*************** MergeAttributes(List *schema, List *supe
*** 1566,1572 ****
  						(errmsg("merging multiple inherited definitions of column \"%s\"",
  								attributeName)));
  				def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
! 				typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod);
  				if (defTypeId != attribute->atttypid ||
  					deftypmod != attribute->atttypmod)
  					ereport(ERROR,
--- 1566,1572 ----
  						(errmsg("merging multiple inherited definitions of column \"%s\"",
  								attributeName)));
  				def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
! 				typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod, false);
  				if (defTypeId != attribute->atttypid ||
  					deftypmod != attribute->atttypmod)
  					ereport(ERROR,
*************** MergeAttributes(List *schema, List *supe
*** 1775,1782 ****
  				   (errmsg("merging column \"%s\" with inherited definition",
  						   attributeName)));
  				def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
! 				typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod);
! 				typenameTypeIdAndMod(NULL, newdef->typeName, &newTypeId, &newtypmod);
  				if (defTypeId != newTypeId || deftypmod != newtypmod)
  					ereport(ERROR,
  							(errcode(ERRCODE_DATATYPE_MISMATCH),
--- 1775,1782 ----
  				   (errmsg("merging column \"%s\" with inherited definition",
  						   attributeName)));
  				def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
! 				typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod, false);
! 				typenameTypeIdAndMod(NULL, newdef->typeName, &newTypeId, &newtypmod, false);
  				if (defTypeId != newTypeId || deftypmod != newtypmod)
  					ereport(ERROR,
  							(errcode(ERRCODE_DATATYPE_MISMATCH),
*************** ATExecAddColumn(List **wqueue, AlteredTa
*** 4463,4469 ****
  			Oid			ccollid;
  
  			/* Child column must match on type, typmod, and collation */
! 			typenameTypeIdAndMod(NULL, colDef->typeName, &ctypeId, &ctypmod);
  			if (ctypeId != childatt->atttypid ||
  				ctypmod != childatt->atttypmod)
  				ereport(ERROR,
--- 4463,4469 ----
  			Oid			ccollid;
  
  			/* Child column must match on type, typmod, and collation */
! 			typenameTypeIdAndMod(NULL, colDef->typeName, &ctypeId, &ctypmod, false);
  			if (ctypeId != childatt->atttypid ||
  				ctypmod != childatt->atttypmod)
  				ereport(ERROR,
*************** ATPrepAlterColumnType(List **wqueue,
*** 7442,7448 ****
  						colName)));
  
  	/* Look up the target type */
! 	typenameTypeIdAndMod(NULL, typeName, &targettype, &targettypmod);
  
  	aclresult = pg_type_aclcheck(targettype, GetUserId(), ACL_USAGE);
  	if (aclresult != ACLCHECK_OK)
--- 7442,7448 ----
  						colName)));
  
  	/* Look up the target type */
! 	typenameTypeIdAndMod(NULL, typeName, &targettype, &targettypmod, false);
  
  	aclresult = pg_type_aclcheck(targettype, GetUserId(), ACL_USAGE);
  	if (aclresult != ACLCHECK_OK)
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
new file mode 100644
index 81c9338..a94dc02
*** a/src/backend/parser/parse_expr.c
--- b/src/backend/parser/parse_expr.c
*************** transformExprRecurse(ParseState *pstate,
*** 184,190 ****
  					int32		targetTypmod;
  
  					typenameTypeIdAndMod(pstate, tc->typeName,
! 										 &targetType, &targetTypmod);
  
  					/*
  					 * If target is a domain over array, work with the base
--- 184,190 ----
  					int32		targetTypmod;
  
  					typenameTypeIdAndMod(pstate, tc->typeName,
! 										 &targetType, &targetTypmod, false);
  
  					/*
  					 * If target is a domain over array, work with the base
*************** transformXmlSerialize(ParseState *pstate
*** 2052,2058 ****
  													 XMLOID,
  													 "XMLSERIALIZE"));
  
! 	typenameTypeIdAndMod(pstate, xs->typeName, &targetType, &targetTypmod);
  
  	xexpr->xmloption = xs->xmloption;
  	xexpr->location = xs->location;
--- 2052,2058 ----
  													 XMLOID,
  													 "XMLSERIALIZE"));
  
! 	typenameTypeIdAndMod(pstate, xs->typeName, &targetType, &targetTypmod, false);
  
  	xexpr->xmloption = xs->xmloption;
  	xexpr->location = xs->location;
*************** transformTypeCast(ParseState *pstate, Ty
*** 2222,2228 ****
  	int32		targetTypmod;
  	int			location;
  
! 	typenameTypeIdAndMod(pstate, tc->typeName, &targetType, &targetTypmod);
  
  	if (inputType == InvalidOid)
  		return expr;			/* do nothing if NULL input */
--- 2222,2228 ----
  	int32		targetTypmod;
  	int			location;
  
! 	typenameTypeIdAndMod(pstate, tc->typeName, &targetType, &targetTypmod, false);
  
  	if (inputType == InvalidOid)
  		return expr;			/* do nothing if NULL input */
diff --git a/src/backend/parser/parse_oper.c b/src/backend/parser/parse_oper.c
new file mode 100644
index 99dbd30..a2b712d
*** a/src/backend/parser/parse_oper.c
--- b/src/backend/parser/parse_oper.c
*************** oper(ParseState *pstate, List *opname, O
*** 407,413 ****
  		FuncCandidateList clist;
  
  		/* Get binary operators of given name */
! 		clist = OpernameGetCandidates(opname, 'b');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 407,413 ----
  		FuncCandidateList clist;
  
  		/* Get binary operators of given name */
! 		clist = OpernameGetCandidates(opname, 'b', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
*************** right_oper(ParseState *pstate, List *op,
*** 553,559 ****
  		FuncCandidateList clist;
  
  		/* Get postfix operators of given name */
! 		clist = OpernameGetCandidates(op, 'r');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 553,559 ----
  		FuncCandidateList clist;
  
  		/* Get postfix operators of given name */
! 		clist = OpernameGetCandidates(op, 'r', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
*************** left_oper(ParseState *pstate, List *op, 
*** 631,637 ****
  		FuncCandidateList clist;
  
  		/* Get prefix operators of given name */
! 		clist = OpernameGetCandidates(op, 'l');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 631,637 ----
  		FuncCandidateList clist;
  
  		/* Get prefix operators of given name */
! 		clist = OpernameGetCandidates(op, 'l', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
diff --git a/src/backend/parser/parse_relation.c b/src/backend/parser/parse_relation.c
new file mode 100644
index 8760952..51c13b8
*** a/src/backend/parser/parse_relation.c
--- b/src/backend/parser/parse_relation.c
*************** addRangeTableEntryForFunction(ParseState
*** 1340,1346 ****
  									attrname),
  							 parser_errposition(pstate, n->location)));
  				typenameTypeIdAndMod(pstate, n->typeName,
! 									 &attrtype, &attrtypmod);
  				attrcollation = GetColumnDefCollation(pstate, n, attrtype);
  				TupleDescInitEntry(tupdesc,
  								   (AttrNumber) i,
--- 1340,1346 ----
  									attrname),
  							 parser_errposition(pstate, n->location)));
  				typenameTypeIdAndMod(pstate, n->typeName,
! 									 &attrtype, &attrtypmod, false);
  				attrcollation = GetColumnDefCollation(pstate, n, attrtype);
  				TupleDescInitEntry(tupdesc,
  								   (AttrNumber) i,
diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
new file mode 100644
index b329dfb..4ccc82b
*** a/src/backend/parser/parse_type.c
--- b/src/backend/parser/parse_type.c
***************
*** 29,35 ****
  
  
  static int32 typenameTypeMod(ParseState *pstate, const TypeName *typeName,
! 				Type typ);
  
  
  /*
--- 29,35 ----
  
  
  static int32 typenameTypeMod(ParseState *pstate, const TypeName *typeName,
! 							 Type typ);
  
  
  /*
*************** typenameTypeId(ParseState *pstate, const
*** 287,299 ****
   */
  void
  typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName,
! 					 Oid *typeid_p, int32 *typmod_p)
  {
  	Type		tup;
  
! 	tup = typenameType(pstate, typeName, typmod_p);
! 	*typeid_p = HeapTupleGetOid(tup);
! 	ReleaseSysCache(tup);
  }
  
  /*
--- 287,314 ----
   */
  void
  typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName,
! 					 Oid *typeid_p, int32 *typmod_p,
! 					 bool missing_ok)
  {
  	Type		tup;
  
! 	if (missing_ok)
! 	{
! 		tup = LookupTypeName(pstate, typeName, typmod_p, missing_ok);
! 		if (tup == NULL || !((Form_pg_type) GETSTRUCT(tup))->typisdefined)
! 			*typeid_p = InvalidOid;
! 		else
! 			*typeid_p = HeapTupleGetOid(tup);
! 
! 		if (tup)
! 			ReleaseSysCache(tup);
! 	}
! 	else
! 	{
! 		tup = typenameType(pstate, typeName, typmod_p);
! 		*typeid_p = HeapTupleGetOid(tup);
! 		ReleaseSysCache(tup);
! 	}
  }
  
  /*
*************** pts_error_callback(void *arg)
*** 706,714 ****
   * Given a string that is supposed to be a SQL-compatible type declaration,
   * such as "int4" or "integer" or "character varying(32)", parse
   * the string and convert it to a type OID and type modifier.
   */
  void
! parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p)
  {
  	StringInfoData buf;
  	List	   *raw_parsetree_list;
--- 721,731 ----
   * Given a string that is supposed to be a SQL-compatible type declaration,
   * such as "int4" or "integer" or "character varying(32)", parse
   * the string and convert it to a type OID and type modifier.
+  * If the type name is not found, return InvalidOid if missing_ok
+  * = true, otherwise raise an error.
   */
  void
! parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p, bool missing_ok)
  {
  	StringInfoData buf;
  	List	   *raw_parsetree_list;
*************** parseTypeString(const char *str, Oid *ty
*** 782,788 ****
  	if (typeName->setof)
  		goto fail;
  
! 	typenameTypeIdAndMod(NULL, typeName, typeid_p, typmod_p);
  
  	pfree(buf.data);
  
--- 799,805 ----
  	if (typeName->setof)
  		goto fail;
  
! 	typenameTypeIdAndMod(NULL, typeName, typeid_p, typmod_p, missing_ok);
  
  	pfree(buf.data);
  
diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
new file mode 100644
index 5d73562..70e5a87
*** a/src/backend/utils/adt/regproc.c
--- b/src/backend/utils/adt/regproc.c
***************
*** 44,50 ****
  static char *format_operator_internal(Oid operator_oid, bool force_qualify);
  static char *format_procedure_internal(Oid procedure_oid, bool force_qualify);
  static void parseNameAndArgTypes(const char *string, bool allowNone,
! 					 List **names, int *nargs, Oid *argtypes);
  
  
  /*****************************************************************************
--- 44,54 ----
  static char *format_operator_internal(Oid operator_oid, bool force_qualify);
  static char *format_procedure_internal(Oid procedure_oid, bool force_qualify);
  static void parseNameAndArgTypes(const char *string, bool allowNone,
! 								 List **names, int *nargs, Oid *argtypes);
! static Oid regoper_guts(char *opr_name_or_oid, bool missing_ok);
! static Oid regproc_guts(char *pro_name_or_oid, bool missing_ok);
! static Oid regclass_guts(char *class_name_or_oid, bool missing_ok);
! static Oid regtype_guts(char *typ_name_or_oid, bool missing_ok);
  
  
  /*****************************************************************************
*************** Datum
*** 63,75 ****
  regprocin(PG_FUNCTION_ARGS)
  {
  	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
  	RegProcedure result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '-' ? */
  	if (strcmp(pro_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (pro_name_or_oid[0] >= '0' &&
--- 67,109 ----
  regprocin(PG_FUNCTION_ARGS)
  {
  	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regproc_guts(pro_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regproc	- converts "proname" to proc OID
+  *
+  * Diffrence from regprocin is, this does not throw an error if the proname
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regproc(PG_FUNCTION_ARGS)
+ {
+ 	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regproc_guts(pro_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * Guts of regoperin and to_regproc.
+  * If missing_ok is true, returns InvalidOid when the proname does not exist.
+  */
+ static Oid
+ regproc_guts(char *pro_name_or_oid, bool missing_ok)
+ {
  	RegProcedure result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '-' ? */
  	if (strcmp(pro_name_or_oid, "-") == 0)
! 		return InvalidOid;
  
  	/* Numeric OID? */
  	if (pro_name_or_oid[0] >= '0' &&
*************** regprocin(PG_FUNCTION_ARGS)
*** 77,84 ****
  		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(pro_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a name, possibly schema-qualified */
--- 111,118 ----
  		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(pro_name_or_oid)));
! 		return result;
  	}
  
  	/* Else it's a name, possibly schema-qualified */
*************** regprocin(PG_FUNCTION_ARGS)
*** 117,133 ****
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 
  		else if (matches > 1)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one function named \"%s\"",
! 							pro_name_or_oid)));
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 151,176 ----
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 		{
! 			if (missing_ok)
! 				return InvalidOid;
! 			else
! 				ereport(ERROR,
! 						(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 						 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 		}
  		else if (matches > 1)
! 		{
! 			if (missing_ok)
! 				return InvalidOid;
! 			else
! 				ereport(ERROR,
! 						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 						 errmsg("more than one function named \"%s\"",
! 								pro_name_or_oid)));
! 		}
  
! 		return result;
  	}
  
  	/*
*************** regprocin(PG_FUNCTION_ARGS)
*** 135,155 ****
  	 * pg_proc entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(pro_name_or_oid);
! 	clist = FuncnameGetCandidates(names, -1, NIL, false, false, false);
  
  	if (clist == NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
  	else if (clist->next != NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 				 errmsg("more than one function named \"%s\"",
! 						pro_name_or_oid)));
  
  	result = clist->oid;
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 178,208 ----
  	 * pg_proc entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(pro_name_or_oid);
! 	clist = FuncnameGetCandidates(names, -1, NIL, false, false, missing_ok);
  
  	if (clist == NULL)
! 	{
! 		if (missing_ok)
! 			return InvalidOid;
! 		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 	}
  	else if (clist->next != NULL)
! 	{
! 		if (missing_ok)
! 			return InvalidOid;
! 		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one function named \"%s\"",
! 							pro_name_or_oid)));
! 	}
  
  	result = clist->oid;
  
! 	return result;
  }
  
  /*
*************** regprocedurein(PG_FUNCTION_ARGS)
*** 263,269 ****
  		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(pro_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
--- 316,322 ----
  		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(pro_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
*************** Datum
*** 431,443 ****
  regoperin(PG_FUNCTION_ARGS)
  {
  	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
  	Oid			result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '0' ? */
  	if (strcmp(opr_name_or_oid, "0") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (opr_name_or_oid[0] >= '0' &&
--- 484,526 ----
  regoperin(PG_FUNCTION_ARGS)
  {
  	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regoper_guts(opr_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regoper		- converts "oprname" to operator OID
+  *
+  * Diffrence from regoper is, this does not throw an error if the operator
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regoper(PG_FUNCTION_ARGS)
+ {
+ 	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regoper_guts(opr_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * Guts of regoperin and to_regoper.
+  * If missing_ok is true, returns InvalidOid when the operator does not exist.
+  */
+ static Oid
+ regoper_guts(char *opr_name_or_oid, bool missing_ok)
+ {
  	Oid			result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '0' ? */
  	if (strcmp(opr_name_or_oid, "0") == 0)
! 		return InvalidOid;
  
  	/* Numeric OID? */
  	if (opr_name_or_oid[0] >= '0' &&
*************** regoperin(PG_FUNCTION_ARGS)
*** 445,452 ****
  		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(opr_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a name, possibly schema-qualified */
--- 528,535 ----
  		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(opr_name_or_oid)));
! 		return result;
  	}
  
  	/* Else it's a name, possibly schema-qualified */
*************** regoperin(PG_FUNCTION_ARGS)
*** 485,500 ****
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("operator does not exist: %s", opr_name_or_oid)));
  		else if (matches > 1)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one operator named %s",
! 							opr_name_or_oid)));
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 568,593 ----
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 		{
! 			if (missing_ok)
! 				return InvalidOid;
! 			else
! 				ereport(ERROR,
! 						(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 						 errmsg("operator does not exist: %s", opr_name_or_oid)));
! 		}
  		else if (matches > 1)
! 		{
! 			if (missing_ok)
! 				return InvalidOid;
! 			else
! 				ereport(ERROR,
! 						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 						 errmsg("more than one operator named %s",
! 								opr_name_or_oid)));
! 		}
  
! 		return result;
  	}
  
  	/*
*************** regoperin(PG_FUNCTION_ARGS)
*** 502,522 ****
  	 * pg_operator entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(opr_name_or_oid);
! 	clist = OpernameGetCandidates(names, '\0');
  
  	if (clist == NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("operator does not exist: %s", opr_name_or_oid)));
  	else if (clist->next != NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 				 errmsg("more than one operator named %s",
! 						opr_name_or_oid)));
  
  	result = clist->oid;
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 595,625 ----
  	 * pg_operator entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(opr_name_or_oid);
! 	clist = OpernameGetCandidates(names, '\0', missing_ok);
  
  	if (clist == NULL)
! 	{
! 		if (missing_ok)
! 			return InvalidOid;
! 		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("operator does not exist: %s", opr_name_or_oid)));
! 	}
  	else if (clist->next != NULL)
! 	{
! 		if (missing_ok)
! 			return InvalidOid;
! 		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one operator named %s",
! 							opr_name_or_oid)));
! 	}
  
  	result = clist->oid;
  
! 	return result;
  }
  
  /*
*************** regoperout(PG_FUNCTION_ARGS)
*** 558,564 ****
  			 * qualify it.
  			 */
  			clist = OpernameGetCandidates(list_make1(makeString(oprname)),
! 										  '\0');
  			if (clist != NULL && clist->next == NULL &&
  				clist->oid == oprid)
  				result = pstrdup(oprname);
--- 661,667 ----
  			 * qualify it.
  			 */
  			clist = OpernameGetCandidates(list_make1(makeString(oprname)),
! 										  '\0', false);
  			if (clist != NULL && clist->next == NULL &&
  				clist->oid == oprid)
  				result = pstrdup(oprname);
*************** regoperatorin(PG_FUNCTION_ARGS)
*** 635,641 ****
  		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(opr_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
--- 738,744 ----
  		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(opr_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
*************** Datum
*** 804,815 ****
  regclassin(PG_FUNCTION_ARGS)
  {
  	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
  	Oid			result = InvalidOid;
  	List	   *names;
  
  	/* '-' ? */
  	if (strcmp(class_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (class_name_or_oid[0] >= '0' &&
--- 907,948 ----
  regclassin(PG_FUNCTION_ARGS)
  {
  	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regclass_guts(class_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regclass		- converts "classname" to class OID
+  *
+  * Diffrence from regclassin is, this does not throw an error if the classname
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regclass(PG_FUNCTION_ARGS)
+ {
+ 	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regclass_guts(class_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * Guts of regclassin and to_regclass.
+  * If missing_ok is true, returns InvalidOid when the classname does not exist.
+  */
+ static Oid
+ regclass_guts(char *class_name_or_oid, bool missing_ok)
+ {
  	Oid			result = InvalidOid;
  	List	   *names;
  
  	/* '-' ? */
  	if (strcmp(class_name_or_oid, "-") == 0)
! 		return result;
  
  	/* Numeric OID? */
  	if (class_name_or_oid[0] >= '0' &&
*************** regclassin(PG_FUNCTION_ARGS)
*** 817,824 ****
  		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										CStringGetDatum(class_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a name, possibly schema-qualified */
--- 950,957 ----
  		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(class_name_or_oid)));
! 		return result;
  	}
  
  	/* Else it's a name, possibly schema-qualified */
*************** regclassin(PG_FUNCTION_ARGS)
*** 848,863 ****
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
  		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_TABLE),
! 			   errmsg("relation \"%s\" does not exist", class_name_or_oid)));
  
  		/* We assume there can be only one match */
  
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 981,999 ----
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
  		else
! 			if (missing_ok)
! 				return InvalidOid;
! 			else
! 				ereport(ERROR,
! 						(errcode(ERRCODE_UNDEFINED_TABLE),
! 						 errmsg("relation \"%s\" does not exist", class_name_or_oid)));
  
  		/* We assume there can be only one match */
  
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		return result;
  	}
  
  	/*
*************** regclassin(PG_FUNCTION_ARGS)
*** 865,875 ****
  	 * pg_class entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(class_name_or_oid);
  
  	/* We might not even have permissions on this relation; don't lock it. */
! 	result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, false);
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 1001,1013 ----
  	 * pg_class entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(class_name_or_oid);
+ 	if (names == NIL)
+ 		return InvalidOid;
  
  	/* We might not even have permissions on this relation; don't lock it. */
! 	result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, missing_ok);
  
! 	return result;
  }
  
  /*
*************** Datum
*** 968,979 ****
  regtypein(PG_FUNCTION_ARGS)
  {
  	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
  	Oid			result = InvalidOid;
  	int32		typmod;
  
  	/* '-' ? */
  	if (strcmp(typ_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (typ_name_or_oid[0] >= '0' &&
--- 1106,1147 ----
  regtypein(PG_FUNCTION_ARGS)
  {
  	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regtype_guts(typ_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regtype		- converts "typename" to type OID
+  *
+  * Diffrence from regtypein is, this does not throw an error if the typename
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regtype(PG_FUNCTION_ARGS)
+ {
+ 	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regtype_guts(typ_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * Guts of regtypein and to_regtype.
+  * If missing_ok is true, returns InvalidOid when the typename does not exist.
+  */
+ static Oid
+ regtype_guts(char *typ_name_or_oid, bool missing_ok)
+ {
  	Oid			result = InvalidOid;
  	int32		typmod;
  
  	/* '-' ? */
  	if (strcmp(typ_name_or_oid, "-") == 0)
! 		return InvalidOid;
  
  	/* Numeric OID? */
  	if (typ_name_or_oid[0] >= '0' &&
*************** regtypein(PG_FUNCTION_ARGS)
*** 981,988 ****
  		strspn(typ_name_or_oid, "0123456789") == strlen(typ_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(typ_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a type name, possibly schema-qualified or decorated */
--- 1149,1156 ----
  		strspn(typ_name_or_oid, "0123456789") == strlen(typ_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(typ_name_or_oid)));
! 		return result;
  	}
  
  	/* Else it's a type name, possibly schema-qualified or decorated */
*************** regtypein(PG_FUNCTION_ARGS)
*** 1011,1017 ****
  
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
! 		else
  			ereport(ERROR,
  					(errcode(ERRCODE_UNDEFINED_OBJECT),
  					 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
--- 1179,1185 ----
  
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
! 		else if (!missing_ok)
  			ereport(ERROR,
  					(errcode(ERRCODE_UNDEFINED_OBJECT),
  					 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
*************** regtypein(PG_FUNCTION_ARGS)
*** 1021,1036 ****
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
  	 * Normal case: invoke the full parser to deal with special cases such as
  	 * array syntax.
  	 */
! 	parseTypeString(typ_name_or_oid, &result, &typmod);
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 1189,1204 ----
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		return result;
  	}
  
  	/*
  	 * Normal case: invoke the full parser to deal with special cases such as
  	 * array syntax.
  	 */
! 	parseTypeString(typ_name_or_oid, &result, &typmod, missing_ok);
  
! 	return result;
  }
  
  /*
*************** regconfigin(PG_FUNCTION_ARGS)
*** 1130,1136 ****
  		strspn(cfg_name_or_oid, "0123456789") == strlen(cfg_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(cfg_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
--- 1298,1304 ----
  		strspn(cfg_name_or_oid, "0123456789") == strlen(cfg_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(cfg_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
*************** regdictionaryin(PG_FUNCTION_ARGS)
*** 1240,1246 ****
  		strspn(dict_name_or_oid, "0123456789") == strlen(dict_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										 CStringGetDatum(dict_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
--- 1408,1414 ----
  		strspn(dict_name_or_oid, "0123456789") == strlen(dict_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(dict_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
*************** parseNameAndArgTypes(const char *string,
*** 1523,1529 ****
  		else
  		{
  			/* Use full parser to resolve the type name */
! 			parseTypeString(typename, &typeid, &typmod);
  		}
  		if (*nargs >= FUNC_MAX_ARGS)
  			ereport(ERROR,
--- 1691,1697 ----
  		else
  		{
  			/* Use full parser to resolve the type name */
! 			parseTypeString(typename, &typeid, &typmod, false);
  		}
  		if (*nargs >= FUNC_MAX_ARGS)
  			ereport(ERROR,
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
new file mode 100644
index 2cc8f90..7c78aaa
*** a/src/backend/utils/misc/guc.c
--- b/src/backend/utils/misc/guc.c
*************** flatten_set_variable_args(const char *na
*** 6421,6427 ****
  					Datum		interval;
  					char	   *intervalout;
  
! 					typenameTypeIdAndMod(NULL, typeName, &typoid, &typmod);
  					Assert(typoid == INTERVALOID);
  
  					interval =
--- 6421,6427 ----
  					Datum		interval;
  					char	   *intervalout;
  
! 					typenameTypeIdAndMod(NULL, typeName, &typoid, &typmod, false);
  					Assert(typoid == INTERVALOID);
  
  					interval =
diff --git a/src/include/catalog/namespace.h b/src/include/catalog/namespace.h
new file mode 100644
index b30e5e8..350fafe
*** a/src/include/catalog/namespace.h
--- b/src/include/catalog/namespace.h
*************** extern FuncCandidateList FuncnameGetCand
*** 76,82 ****
  extern bool FunctionIsVisible(Oid funcid);
  
  extern Oid	OpernameGetOprid(List *names, Oid oprleft, Oid oprright);
! extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind);
  extern bool OperatorIsVisible(Oid oprid);
  
  extern Oid	OpclassnameGetOpcid(Oid amid, const char *opcname);
--- 76,83 ----
  extern bool FunctionIsVisible(Oid funcid);
  
  extern Oid	OpernameGetOprid(List *names, Oid oprleft, Oid oprright);
! extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind,
! 					  bool missing_ok);
  extern bool OperatorIsVisible(Oid oprid);
  
  extern Oid	OpclassnameGetOpcid(Oid amid, const char *opcname);
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
new file mode 100644
index ad9774c..d452ae0
*** a/src/include/catalog/pg_proc.h
--- b/src/include/catalog/pg_proc.h
*************** DATA(insert OID =  44 (  regprocin		   P
*** 173,178 ****
--- 173,180 ----
  DESCR("I/O");
  DATA(insert OID =  45 (  regprocout		   PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "24" _null_ _null_ _null_ _null_ regprocout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3196 (  to_regproc		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 24 "2275" _null_ _null_ _null_ _null_ to_regproc _null_ _null_ _null_ ));
+ DESCR("convert proname to regproc");
  DATA(insert OID =  46 (  textin			   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 25 "2275" _null_ _null_ _null_ _null_ textin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID =  47 (  textout		   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2275 "25" _null_ _null_ _null_ _null_ textout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2214 (  regoperin			PG
*** 3298,3303 ****
--- 3300,3307 ----
  DESCR("I/O");
  DATA(insert OID = 2215 (  regoperout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2203" _null_ _null_ _null_ _null_ regoperout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3180 (  to_regoper		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2203 "2275" _null_ _null_ _null_ _null_ to_regoper _null_ _null_ _null_ ));
+ DESCR("convert operator name to regoper");
  DATA(insert OID = 2216 (  regoperatorin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2204 "2275" _null_ _null_ _null_ _null_ regoperatorin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2217 (  regoperatorout	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2204" _null_ _null_ _null_ _null_ regoperatorout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2218 (  regclassin		PG
*** 3306,3315 ****
--- 3310,3323 ----
  DESCR("I/O");
  DATA(insert OID = 2219 (  regclassout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2205" _null_ _null_ _null_ _null_ regclassout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3197 (  to_regclass		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "2275" _null_ _null_ _null_ _null_ to_regclass _null_ _null_ _null_ ));
+ DESCR("convert classname to regclass");
  DATA(insert OID = 2220 (  regtypein			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ regtypein _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2221 (  regtypeout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2206" _null_ _null_ _null_ _null_ regtypeout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3195 (  to_regtype		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ to_regtype _null_ _null_ _null_ ));
+ DESCR("convert type name to regtype");
  DATA(insert OID = 1079 (  regclass			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "25" _null_ _null_ _null_ _null_	text_regclass _null_ _null_ _null_ ));
  DESCR("convert text to regclass");
  
diff --git a/src/include/parser/parse_type.h b/src/include/parser/parse_type.h
new file mode 100644
index ab73148..b45538a
*** a/src/include/parser/parse_type.h
--- b/src/include/parser/parse_type.h
*************** extern Type typenameType(ParseState *pst
*** 27,33 ****
  			 int32 *typmod_p);
  extern Oid	typenameTypeId(ParseState *pstate, const TypeName *typeName);
  extern void typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName,
! 					 Oid *typeid_p, int32 *typmod_p);
  
  extern char *TypeNameToString(const TypeName *typeName);
  extern char *TypeNameListToString(List *typenames);
--- 27,33 ----
  			 int32 *typmod_p);
  extern Oid	typenameTypeId(ParseState *pstate, const TypeName *typeName);
  extern void typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName,
! 					 Oid *typeid_p, int32 *typmod_p, bool missing_ok);
  
  extern char *TypeNameToString(const TypeName *typeName);
  extern char *TypeNameListToString(List *typenames);
*************** extern Datum stringTypeDatum(Type tp, ch
*** 47,53 ****
  
  extern Oid	typeidTypeRelid(Oid type_id);
  
! extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p);
  
  #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
  
--- 47,53 ----
  
  extern Oid	typeidTypeRelid(Oid type_id);
  
! extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p, bool missing_ok);
  
  #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
  
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
new file mode 100644
index b90d88d..85dee8a
*** a/src/include/utils/builtins.h
--- b/src/include/utils/builtins.h
*************** extern char *regexp_fixed_prefix(text *t
*** 597,602 ****
--- 597,603 ----
  /* regproc.c */
  extern Datum regprocin(PG_FUNCTION_ARGS);
  extern Datum regprocout(PG_FUNCTION_ARGS);
+ extern Datum to_regproc(PG_FUNCTION_ARGS);
  extern Datum regprocrecv(PG_FUNCTION_ARGS);
  extern Datum regprocsend(PG_FUNCTION_ARGS);
  extern Datum regprocedurein(PG_FUNCTION_ARGS);
*************** extern Datum regoperin(PG_FUNCTION_ARGS)
*** 607,612 ****
--- 608,614 ----
  extern Datum regoperout(PG_FUNCTION_ARGS);
  extern Datum regoperrecv(PG_FUNCTION_ARGS);
  extern Datum regopersend(PG_FUNCTION_ARGS);
+ extern Datum to_regoper(PG_FUNCTION_ARGS);
  extern Datum regoperatorin(PG_FUNCTION_ARGS);
  extern Datum regoperatorout(PG_FUNCTION_ARGS);
  extern Datum regoperatorrecv(PG_FUNCTION_ARGS);
*************** extern Datum regclassin(PG_FUNCTION_ARGS
*** 615,624 ****
--- 617,628 ----
  extern Datum regclassout(PG_FUNCTION_ARGS);
  extern Datum regclassrecv(PG_FUNCTION_ARGS);
  extern Datum regclasssend(PG_FUNCTION_ARGS);
+ extern Datum to_regclass(PG_FUNCTION_ARGS);
  extern Datum regtypein(PG_FUNCTION_ARGS);
  extern Datum regtypeout(PG_FUNCTION_ARGS);
  extern Datum regtyperecv(PG_FUNCTION_ARGS);
  extern Datum regtypesend(PG_FUNCTION_ARGS);
+ extern Datum to_regtype(PG_FUNCTION_ARGS);
  extern Datum regconfigin(PG_FUNCTION_ARGS);
  extern Datum regconfigout(PG_FUNCTION_ARGS);
  extern Datum regconfigrecv(PG_FUNCTION_ARGS);
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
new file mode 100644
index a81c185..5a92ee0
*** a/src/pl/plperl/plperl.c
--- b/src/pl/plperl/plperl.c
*************** plperl_spi_prepare(char *query, int argc
*** 3401,3407 ****
  			char	   *typstr;
  
  			typstr = sv2cstr(argv[i]);
! 			parseTypeString(typstr, &typId, &typmod);
  			pfree(typstr);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
--- 3401,3407 ----
  			char	   *typstr;
  
  			typstr = sv2cstr(argv[i]);
! 			parseTypeString(typstr, &typId, &typmod, false);
  			pfree(typstr);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
new file mode 100644
index c0cb585..1862293
*** a/src/pl/plpgsql/src/pl_gram.y
--- b/src/pl/plpgsql/src/pl_gram.y
*************** parse_datatype(const char *string, int l
*** 3462,3468 ****
  	error_context_stack = &syntax_errcontext;
  
  	/* Let the main parser try to parse it under standard SQL rules */
! 	parseTypeString(string, &type_id, &typmod);
  
  	/* Restore former ereport callback */
  	error_context_stack = syntax_errcontext.previous;
--- 3462,3468 ----
  	error_context_stack = &syntax_errcontext;
  
  	/* Let the main parser try to parse it under standard SQL rules */
! 	parseTypeString(string, &type_id, &typmod, false);
  
  	/* Restore former ereport callback */
  	error_context_stack = syntax_errcontext.previous;
diff --git a/src/pl/plpython/plpy_spi.c b/src/pl/plpython/plpy_spi.c
new file mode 100644
index 982bf84..060d514
*** a/src/pl/plpython/plpy_spi.c
--- b/src/pl/plpython/plpy_spi.c
*************** PLy_spi_prepare(PyObject *self, PyObject
*** 113,119 ****
  			 *information for input conversion.
  			 ********************************************************/
  
! 			parseTypeString(sptr, &typeId, &typmod);
  
  			typeTup = SearchSysCache1(TYPEOID,
  									  ObjectIdGetDatum(typeId));
--- 113,119 ----
  			 *information for input conversion.
  			 ********************************************************/
  
! 			parseTypeString(sptr, &typeId, &typmod, false);
  
  			typeTup = SearchSysCache1(TYPEOID,
  									  ObjectIdGetDatum(typeId));
diff --git a/src/pl/tcl/pltcl.c b/src/pl/tcl/pltcl.c
new file mode 100644
index 0538038..c89ee7a
*** a/src/pl/tcl/pltcl.c
--- b/src/pl/tcl/pltcl.c
*************** pltcl_SPI_prepare(ClientData cdata, Tcl_
*** 2161,2167 ****
  						typIOParam;
  			int32		typmod;
  
! 			parseTypeString(args[i], &typId, &typmod);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
  
--- 2161,2167 ----
  						typIOParam;
  			int32		typmod;
  
! 			parseTypeString(args[i], &typId, &typmod, false);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
  
diff --git a/src/test/regress/expected/regproc.out b/src/test/regress/expected/regproc.out
new file mode 100644
index ...80a1e29
*** a/src/test/regress/expected/regproc.out
--- b/src/test/regress/expected/regproc.out
***************
*** 0 ****
--- 1,188 ----
+ --
+ -- regproc
+ --
+ /* Objects exist, ok. */
+ -- without schemaname
+ SELECT regoper('||/');
+  regoper 
+ ---------
+  ||/
+ (1 row)
+ 
+ SELECT regproc('now');
+  regproc 
+ ---------
+  now
+ (1 row)
+ 
+ SELECT regclass('pg_class');
+  regclass 
+ ----------
+  pg_class
+ (1 row)
+ 
+ SELECT regtype('integer');
+  regtype 
+ ---------
+  integer
+ (1 row)
+ 
+ SELECT to_regoper('||/');
+  to_regoper 
+ ------------
+  ||/
+ (1 row)
+ 
+ SELECT to_regproc('now');
+  to_regproc 
+ ------------
+  now
+ (1 row)
+ 
+ SELECT to_regclass('pg_class');
+  to_regclass 
+ -------------
+  pg_class
+ (1 row)
+ 
+ SELECT to_regtype('int4');
+  to_regtype 
+ ------------
+  integer
+ (1 row)
+ 
+ -- with schemaname
+ SELECT regoper('pg_catalog.||/');
+  regoper 
+ ---------
+  ||/
+ (1 row)
+ 
+ SELECT regproc('pg_catalog.now');
+  regproc 
+ ---------
+  now
+ (1 row)
+ 
+ SELECT regclass('pg_catalog.pg_class');
+  regclass 
+ ----------
+  pg_class
+ (1 row)
+ 
+ SELECT regtype('pg_catalog.int4');
+  regtype 
+ ---------
+  integer
+ (1 row)
+ 
+ SELECT to_regoper('pg_catalog.||/');
+  to_regoper 
+ ------------
+  ||/
+ (1 row)
+ 
+ SELECT to_regproc('pg_catalog.now');
+  to_regproc 
+ ------------
+  now
+ (1 row)
+ 
+ SELECT to_regclass('pg_catalog.pg_class');
+  to_regclass 
+ -------------
+  pg_class
+ (1 row)
+ 
+ SELECT to_regtype('pg_catalog.int4');
+  to_regtype 
+ ------------
+  integer
+ (1 row)
+ 
+ /* Objects don't exist, error. */
+ -- without schemaname
+ SELECT regoper('||//');
+ ERROR:  operator does not exist: ||//
+ LINE 3: SELECT regoper('||//');
+                        ^
+ SELECT regproc('know');
+ ERROR:  function "know" does not exist
+ LINE 1: SELECT regproc('know');
+                        ^
+ SELECT regclass('pg_classes');
+ ERROR:  relation "pg_classes" does not exist
+ LINE 1: SELECT regclass('pg_classes');
+                         ^
+ SELECT regtype('int3');
+ ERROR:  type "int3" does not exist
+ LINE 1: SELECT regtype('int3');
+                        ^
+ -- with schemaname
+ SELECT regoper('ng_catalog.||/');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regoper('ng_catalog.||/');
+                        ^
+ SELECT regproc('ng_catalog.now');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regproc('ng_catalog.now');
+                        ^
+ SELECT regclass('ng_catalog.pg_class');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regclass('ng_catalog.pg_class');
+                         ^
+ SELECT regtype('ng_catalog.int4');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regtype('ng_catalog.int4');
+                        ^
+ /* Objects don't exist, but no error. */
+ -- without schemaname
+ SELECT to_regoper('||//');
+  to_regoper 
+ ------------
+  0
+ (1 row)
+ 
+ SELECT to_regproc('know');
+  to_regproc 
+ ------------
+  -
+ (1 row)
+ 
+ SELECT to_regclass('pg_classes');
+  to_regclass 
+ -------------
+  -
+ (1 row)
+ 
+ SELECT to_regtype('int3');
+  to_regtype 
+ ------------
+  -
+ (1 row)
+ 
+ -- with schemaname
+ SELECT to_regoper('ng_catalog.||/');
+  to_regoper 
+ ------------
+  0
+ (1 row)
+ 
+ SELECT to_regproc('ng_catalog.now');
+  to_regproc 
+ ------------
+  -
+ (1 row)
+ 
+ SELECT to_regclass('ng_catalog.pg_class');
+  to_regclass 
+ -------------
+  -
+ (1 row)
+ 
+ SELECT to_regtype('ng_catalog.int4');
+  to_regtype 
+ ------------
+  -
+ (1 row)
+ 
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
new file mode 100644
index 5758b07..36c1ece
*** a/src/test/regress/parallel_schedule
--- b/src/test/regress/parallel_schedule
*************** test: tablespace
*** 13,19 ****
  # ----------
  # The first group of parallel tests
  # ----------
! test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes
  
  # Depends on things setup during char, varchar and text
  test: strings
--- 13,19 ----
  # ----------
  # The first group of parallel tests
  # ----------
! test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes regproc
  
  # Depends on things setup during char, varchar and text
  test: strings
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
new file mode 100644
index 78348f5..9a54d7c
*** a/src/test/regress/serial_schedule
--- b/src/test/regress/serial_schedule
*************** test: uuid
*** 19,24 ****
--- 19,25 ----
  test: enum
  test: money
  test: rangetypes
+ test: regproc
  test: strings
  test: numerology
  test: point
diff --git a/src/test/regress/sql/regproc.sql b/src/test/regress/sql/regproc.sql
new file mode 100644
index ...2bbcea0
*** a/src/test/regress/sql/regproc.sql
--- b/src/test/regress/sql/regproc.sql
***************
*** 0 ****
--- 1,61 ----
+ --
+ -- regproc
+ --
+ 
+ /* Objects exist, ok. */
+ 
+ -- without schemaname
+ 
+ SELECT regoper('||/');
+ SELECT regproc('now');
+ SELECT regclass('pg_class');
+ SELECT regtype('integer');
+ 
+ SELECT to_regoper('||/');
+ SELECT to_regproc('now');
+ SELECT to_regclass('pg_class');
+ SELECT to_regtype('int4');
+ 
+ -- with schemaname
+ 
+ SELECT regoper('pg_catalog.||/');
+ SELECT regproc('pg_catalog.now');
+ SELECT regclass('pg_catalog.pg_class');
+ SELECT regtype('pg_catalog.int4');
+ 
+ SELECT to_regoper('pg_catalog.||/');
+ SELECT to_regproc('pg_catalog.now');
+ SELECT to_regclass('pg_catalog.pg_class');
+ SELECT to_regtype('pg_catalog.int4');
+ 
+ /* Objects don't exist, error. */
+ 
+ -- without schemaname
+ 
+ SELECT regoper('||//');
+ SELECT regproc('know');
+ SELECT regclass('pg_classes');
+ SELECT regtype('int3');
+ 
+ -- with schemaname
+ 
+ SELECT regoper('ng_catalog.||/');
+ SELECT regproc('ng_catalog.now');
+ SELECT regclass('ng_catalog.pg_class');
+ SELECT regtype('ng_catalog.int4');
+ 
+ /* Objects don't exist, but no error. */
+ 
+ -- without schemaname
+ 
+ SELECT to_regoper('||//');
+ SELECT to_regproc('know');
+ SELECT to_regclass('pg_classes');
+ SELECT to_regtype('int3');
+ 
+ -- with schemaname
+ 
+ SELECT to_regoper('ng_catalog.||/');
+ SELECT to_regproc('ng_catalog.now');
+ SELECT to_regclass('ng_catalog.pg_class');
+ SELECT to_regtype('ng_catalog.int4');

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
new file mode 100644
index 9816163..3bfb233
*** a/doc/src/sgml/func.sgml
--- b/doc/src/sgml/func.sgml
*************** SELECT pg_type_is_visible('myschema.widg
*** 15037,15042 ****
--- 15037,15058 ----
      <primary>collation for</primary>
     </indexterm>
  
+    <indexterm>
+     <primary>to_regclass</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regproc</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regoper</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regtype</primary>
+    </indexterm>
+ 
    <para>
     <xref linkend="functions-info-catalog-table"> lists functions that
     extract information from the system catalogs.
*************** SELECT pg_type_is_visible('myschema.widg
*** 15207,15212 ****
--- 15223,15248 ----
         <entry><type>text</type></entry>
         <entry>get the collation of the argument</entry>
        </row>
+       <row>
+        <entry><literal><function>to_regclass(<parameter>table_name</parameter>)</function></literal></entry>
+        <entry><type>regclass</type></entry>
+        <entry>get the table oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regproc(<parameter>func_name</parameter>)</function></literal></entry>
+        <entry><type>regproc</type></entry>
+        <entry>get the function oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regoper(<parameter>operator_name</parameter>)</function></literal></entry>
+        <entry><type>regoper</type></entry>
+        <entry>get the operator oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regtype(<parameter>type_name</parameter>)</function></literal></entry>
+        <entry><type>regtype</type></entry>
+        <entry>get the type oid</entry>
+       </row>
       </tbody>
      </tgroup>
     </table>
*************** SELECT collation for ('foo' COLLATE "de_
*** 15372,15377 ****
--- 15408,15419 ----
    is not of a collatable data type, then an error is raised.
    </para>
  
+   <para>
+     to_regclass, to_regproc, to_regoper and to_regtype are similar to
+     regclass, regproc, regoper and regtype except that if the requested object
+     is not found, returns InvalidOid, rather than raises an error.
+   </para>
+ 
     <indexterm>
      <primary>col_description</primary>
     </indexterm>
diff --git a/src/backend/access/common/tupdesc.c b/src/backend/access/common/tupdesc.c
new file mode 100644
index db8cb82..e4aa1eb
*** a/src/backend/access/common/tupdesc.c
--- b/src/backend/access/common/tupdesc.c
*************** BuildDescForRelation(List *schema)
*** 617,623 ****
  		attnum++;
  
  		attname = entry->colname;
! 		typenameTypeIdAndMod(NULL, entry->typeName, &atttypid, &atttypmod);
  
  		aclresult = pg_type_aclcheck(atttypid, GetUserId(), ACL_USAGE);
  		if (aclresult != ACLCHECK_OK)
--- 617,623 ----
  		attnum++;
  
  		attname = entry->colname;
! 		typenameTypeIdAndMod(NULL, entry->typeName, &atttypid, &atttypmod, false);
  
  		aclresult = pg_type_aclcheck(atttypid, GetUserId(), ACL_USAGE);
  		if (aclresult != ACLCHECK_OK)
diff --git a/src/backend/catalog/namespace.c b/src/backend/catalog/namespace.c
new file mode 100644
index 6c2a5d2..0253610
*** a/src/backend/catalog/namespace.c
--- b/src/backend/catalog/namespace.c
*************** OpernameGetOprid(List *names, Oid oprlef
*** 1556,1562 ****
   * will be InvalidOid for a prefix or postfix oprkind.	nargs is 2, too.
   */
  FuncCandidateList
! OpernameGetCandidates(List *names, char oprkind)
  {
  	FuncCandidateList resultList = NULL;
  	char	   *resultSpace = NULL;
--- 1556,1562 ----
   * will be InvalidOid for a prefix or postfix oprkind.	nargs is 2, too.
   */
  FuncCandidateList
! OpernameGetCandidates(List *names, char oprkind, bool missing_ok)
  {
  	FuncCandidateList resultList = NULL;
  	char	   *resultSpace = NULL;
*************** OpernameGetCandidates(List *names, char 
*** 1573,1579 ****
  	if (schemaname)
  	{
  		/* use exact schema given */
! 		namespaceId = LookupExplicitNamespace(schemaname, false);
  	}
  	else
  	{
--- 1573,1581 ----
  	if (schemaname)
  	{
  		/* use exact schema given */
! 		namespaceId = LookupExplicitNamespace(schemaname, missing_ok);
!  		if (!OidIsValid(namespaceId))
!  			return NULL;
  	}
  	else
  	{
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
new file mode 100644
index 08b037e..adc2680
*** a/src/backend/commands/tablecmds.c
--- b/src/backend/commands/tablecmds.c
*************** MergeAttributes(List *schema, List *supe
*** 1566,1572 ****
  						(errmsg("merging multiple inherited definitions of column \"%s\"",
  								attributeName)));
  				def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
! 				typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod);
  				if (defTypeId != attribute->atttypid ||
  					deftypmod != attribute->atttypmod)
  					ereport(ERROR,
--- 1566,1572 ----
  						(errmsg("merging multiple inherited definitions of column \"%s\"",
  								attributeName)));
  				def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
! 				typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod, false);
  				if (defTypeId != attribute->atttypid ||
  					deftypmod != attribute->atttypmod)
  					ereport(ERROR,
*************** MergeAttributes(List *schema, List *supe
*** 1775,1782 ****
  				   (errmsg("merging column \"%s\" with inherited definition",
  						   attributeName)));
  				def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
! 				typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod);
! 				typenameTypeIdAndMod(NULL, newdef->typeName, &newTypeId, &newtypmod);
  				if (defTypeId != newTypeId || deftypmod != newtypmod)
  					ereport(ERROR,
  							(errcode(ERRCODE_DATATYPE_MISMATCH),
--- 1775,1782 ----
  				   (errmsg("merging column \"%s\" with inherited definition",
  						   attributeName)));
  				def = (ColumnDef *) list_nth(inhSchema, exist_attno - 1);
! 				typenameTypeIdAndMod(NULL, def->typeName, &defTypeId, &deftypmod, false);
! 				typenameTypeIdAndMod(NULL, newdef->typeName, &newTypeId, &newtypmod, false);
  				if (defTypeId != newTypeId || deftypmod != newtypmod)
  					ereport(ERROR,
  							(errcode(ERRCODE_DATATYPE_MISMATCH),
*************** ATExecAddColumn(List **wqueue, AlteredTa
*** 4463,4469 ****
  			Oid			ccollid;
  
  			/* Child column must match on type, typmod, and collation */
! 			typenameTypeIdAndMod(NULL, colDef->typeName, &ctypeId, &ctypmod);
  			if (ctypeId != childatt->atttypid ||
  				ctypmod != childatt->atttypmod)
  				ereport(ERROR,
--- 4463,4469 ----
  			Oid			ccollid;
  
  			/* Child column must match on type, typmod, and collation */
! 			typenameTypeIdAndMod(NULL, colDef->typeName, &ctypeId, &ctypmod, false);
  			if (ctypeId != childatt->atttypid ||
  				ctypmod != childatt->atttypmod)
  				ereport(ERROR,
*************** ATPrepAlterColumnType(List **wqueue,
*** 7442,7448 ****
  						colName)));
  
  	/* Look up the target type */
! 	typenameTypeIdAndMod(NULL, typeName, &targettype, &targettypmod);
  
  	aclresult = pg_type_aclcheck(targettype, GetUserId(), ACL_USAGE);
  	if (aclresult != ACLCHECK_OK)
--- 7442,7448 ----
  						colName)));
  
  	/* Look up the target type */
! 	typenameTypeIdAndMod(NULL, typeName, &targettype, &targettypmod, false);
  
  	aclresult = pg_type_aclcheck(targettype, GetUserId(), ACL_USAGE);
  	if (aclresult != ACLCHECK_OK)
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
new file mode 100644
index 81c9338..a94dc02
*** a/src/backend/parser/parse_expr.c
--- b/src/backend/parser/parse_expr.c
*************** transformExprRecurse(ParseState *pstate,
*** 184,190 ****
  					int32		targetTypmod;
  
  					typenameTypeIdAndMod(pstate, tc->typeName,
! 										 &targetType, &targetTypmod);
  
  					/*
  					 * If target is a domain over array, work with the base
--- 184,190 ----
  					int32		targetTypmod;
  
  					typenameTypeIdAndMod(pstate, tc->typeName,
! 										 &targetType, &targetTypmod, false);
  
  					/*
  					 * If target is a domain over array, work with the base
*************** transformXmlSerialize(ParseState *pstate
*** 2052,2058 ****
  													 XMLOID,
  													 "XMLSERIALIZE"));
  
! 	typenameTypeIdAndMod(pstate, xs->typeName, &targetType, &targetTypmod);
  
  	xexpr->xmloption = xs->xmloption;
  	xexpr->location = xs->location;
--- 2052,2058 ----
  													 XMLOID,
  													 "XMLSERIALIZE"));
  
! 	typenameTypeIdAndMod(pstate, xs->typeName, &targetType, &targetTypmod, false);
  
  	xexpr->xmloption = xs->xmloption;
  	xexpr->location = xs->location;
*************** transformTypeCast(ParseState *pstate, Ty
*** 2222,2228 ****
  	int32		targetTypmod;
  	int			location;
  
! 	typenameTypeIdAndMod(pstate, tc->typeName, &targetType, &targetTypmod);
  
  	if (inputType == InvalidOid)
  		return expr;			/* do nothing if NULL input */
--- 2222,2228 ----
  	int32		targetTypmod;
  	int			location;
  
! 	typenameTypeIdAndMod(pstate, tc->typeName, &targetType, &targetTypmod, false);
  
  	if (inputType == InvalidOid)
  		return expr;			/* do nothing if NULL input */
diff --git a/src/backend/parser/parse_oper.c b/src/backend/parser/parse_oper.c
new file mode 100644
index 99dbd30..a2b712d
*** a/src/backend/parser/parse_oper.c
--- b/src/backend/parser/parse_oper.c
*************** oper(ParseState *pstate, List *opname, O
*** 407,413 ****
  		FuncCandidateList clist;
  
  		/* Get binary operators of given name */
! 		clist = OpernameGetCandidates(opname, 'b');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 407,413 ----
  		FuncCandidateList clist;
  
  		/* Get binary operators of given name */
! 		clist = OpernameGetCandidates(opname, 'b', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
*************** right_oper(ParseState *pstate, List *op,
*** 553,559 ****
  		FuncCandidateList clist;
  
  		/* Get postfix operators of given name */
! 		clist = OpernameGetCandidates(op, 'r');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 553,559 ----
  		FuncCandidateList clist;
  
  		/* Get postfix operators of given name */
! 		clist = OpernameGetCandidates(op, 'r', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
*************** left_oper(ParseState *pstate, List *op, 
*** 631,637 ****
  		FuncCandidateList clist;
  
  		/* Get prefix operators of given name */
! 		clist = OpernameGetCandidates(op, 'l');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 631,637 ----
  		FuncCandidateList clist;
  
  		/* Get prefix operators of given name */
! 		clist = OpernameGetCandidates(op, 'l', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
diff --git a/src/backend/parser/parse_relation.c b/src/backend/parser/parse_relation.c
new file mode 100644
index 8760952..51c13b8
*** a/src/backend/parser/parse_relation.c
--- b/src/backend/parser/parse_relation.c
*************** addRangeTableEntryForFunction(ParseState
*** 1340,1346 ****
  									attrname),
  							 parser_errposition(pstate, n->location)));
  				typenameTypeIdAndMod(pstate, n->typeName,
! 									 &attrtype, &attrtypmod);
  				attrcollation = GetColumnDefCollation(pstate, n, attrtype);
  				TupleDescInitEntry(tupdesc,
  								   (AttrNumber) i,
--- 1340,1346 ----
  									attrname),
  							 parser_errposition(pstate, n->location)));
  				typenameTypeIdAndMod(pstate, n->typeName,
! 									 &attrtype, &attrtypmod, false);
  				attrcollation = GetColumnDefCollation(pstate, n, attrtype);
  				TupleDescInitEntry(tupdesc,
  								   (AttrNumber) i,
diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
new file mode 100644
index b329dfb..4ccc82b
*** a/src/backend/parser/parse_type.c
--- b/src/backend/parser/parse_type.c
***************
*** 29,35 ****
  
  
  static int32 typenameTypeMod(ParseState *pstate, const TypeName *typeName,
! 				Type typ);
  
  
  /*
--- 29,35 ----
  
  
  static int32 typenameTypeMod(ParseState *pstate, const TypeName *typeName,
! 							 Type typ);
  
  
  /*
*************** typenameTypeId(ParseState *pstate, const
*** 287,299 ****
   */
  void
  typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName,
! 					 Oid *typeid_p, int32 *typmod_p)
  {
  	Type		tup;
  
! 	tup = typenameType(pstate, typeName, typmod_p);
! 	*typeid_p = HeapTupleGetOid(tup);
! 	ReleaseSysCache(tup);
  }
  
  /*
--- 287,314 ----
   */
  void
  typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName,
! 					 Oid *typeid_p, int32 *typmod_p,
! 					 bool missing_ok)
  {
  	Type		tup;
  
! 	if (missing_ok)
! 	{
! 		tup = LookupTypeName(pstate, typeName, typmod_p, missing_ok);
! 		if (tup == NULL || !((Form_pg_type) GETSTRUCT(tup))->typisdefined)
! 			*typeid_p = InvalidOid;
! 		else
! 			*typeid_p = HeapTupleGetOid(tup);
! 
! 		if (tup)
! 			ReleaseSysCache(tup);
! 	}
! 	else
! 	{
! 		tup = typenameType(pstate, typeName, typmod_p);
! 		*typeid_p = HeapTupleGetOid(tup);
! 		ReleaseSysCache(tup);
! 	}
  }
  
  /*
*************** pts_error_callback(void *arg)
*** 706,714 ****
   * Given a string that is supposed to be a SQL-compatible type declaration,
   * such as "int4" or "integer" or "character varying(32)", parse
   * the string and convert it to a type OID and type modifier.
   */
  void
! parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p)
  {
  	StringInfoData buf;
  	List	   *raw_parsetree_list;
--- 721,731 ----
   * Given a string that is supposed to be a SQL-compatible type declaration,
   * such as "int4" or "integer" or "character varying(32)", parse
   * the string and convert it to a type OID and type modifier.
+  * If the type name is not found, return InvalidOid if missing_ok
+  * = true, otherwise raise an error.
   */
  void
! parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p, bool missing_ok)
  {
  	StringInfoData buf;
  	List	   *raw_parsetree_list;
*************** parseTypeString(const char *str, Oid *ty
*** 782,788 ****
  	if (typeName->setof)
  		goto fail;
  
! 	typenameTypeIdAndMod(NULL, typeName, typeid_p, typmod_p);
  
  	pfree(buf.data);
  
--- 799,805 ----
  	if (typeName->setof)
  		goto fail;
  
! 	typenameTypeIdAndMod(NULL, typeName, typeid_p, typmod_p, missing_ok);
  
  	pfree(buf.data);
  
diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
new file mode 100644
index 5d73562..1181a3b
*** a/src/backend/utils/adt/regproc.c
--- b/src/backend/utils/adt/regproc.c
***************
*** 44,50 ****
  static char *format_operator_internal(Oid operator_oid, bool force_qualify);
  static char *format_procedure_internal(Oid procedure_oid, bool force_qualify);
  static void parseNameAndArgTypes(const char *string, bool allowNone,
! 					 List **names, int *nargs, Oid *argtypes);
  
  
  /*****************************************************************************
--- 44,54 ----
  static char *format_operator_internal(Oid operator_oid, bool force_qualify);
  static char *format_procedure_internal(Oid procedure_oid, bool force_qualify);
  static void parseNameAndArgTypes(const char *string, bool allowNone,
! 								 List **names, int *nargs, Oid *argtypes);
! static Oid regoper_guts(char *opr_name_or_oid, bool missing_ok);
! static Oid regproc_guts(char *pro_name_or_oid, bool missing_ok);
! static Oid regclass_guts(char *class_name_or_oid, bool missing_ok);
! static Oid regtype_guts(char *typ_name_or_oid, bool missing_ok);
  
  
  /*****************************************************************************
*************** Datum
*** 63,75 ****
  regprocin(PG_FUNCTION_ARGS)
  {
  	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
  	RegProcedure result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '-' ? */
  	if (strcmp(pro_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (pro_name_or_oid[0] >= '0' &&
--- 67,109 ----
  regprocin(PG_FUNCTION_ARGS)
  {
  	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regproc_guts(pro_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regproc	- converts "proname" to proc OID
+  *
+  * Diffrence from regprocin is, this does not throw an error if the proname
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regproc(PG_FUNCTION_ARGS)
+ {
+ 	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regproc_guts(pro_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * Guts of regoperin and to_regproc.
+  * If missing_ok is true, returns InvalidOid when the proname does not exist.
+  */
+ static Oid
+ regproc_guts(char *pro_name_or_oid, bool missing_ok)
+ {
  	RegProcedure result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '-' ? */
  	if (strcmp(pro_name_or_oid, "-") == 0)
! 		return InvalidOid;
  
  	/* Numeric OID? */
  	if (pro_name_or_oid[0] >= '0' &&
*************** regprocin(PG_FUNCTION_ARGS)
*** 77,84 ****
  		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(pro_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a name, possibly schema-qualified */
--- 111,118 ----
  		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(pro_name_or_oid)));
! 		return result;
  	}
  
  	/* Else it's a name, possibly schema-qualified */
*************** regprocin(PG_FUNCTION_ARGS)
*** 117,133 ****
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 
  		else if (matches > 1)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one function named \"%s\"",
! 							pro_name_or_oid)));
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 151,176 ----
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 		{
! 			if (missing_ok)
! 				return InvalidOid;
! 			else
! 				ereport(ERROR,
! 						(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 						 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 		}
  		else if (matches > 1)
! 		{
! 			if (missing_ok)
! 				return InvalidOid;
! 			else
! 				ereport(ERROR,
! 						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 						 errmsg("more than one function named \"%s\"",
! 								pro_name_or_oid)));
! 		}
  
! 		return result;
  	}
  
  	/*
*************** regprocin(PG_FUNCTION_ARGS)
*** 135,155 ****
  	 * pg_proc entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(pro_name_or_oid);
! 	clist = FuncnameGetCandidates(names, -1, NIL, false, false, false);
  
  	if (clist == NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
  	else if (clist->next != NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 				 errmsg("more than one function named \"%s\"",
! 						pro_name_or_oid)));
  
  	result = clist->oid;
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 178,208 ----
  	 * pg_proc entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(pro_name_or_oid);
! 	clist = FuncnameGetCandidates(names, -1, NIL, false, false, missing_ok);
  
  	if (clist == NULL)
! 	{
! 		if (missing_ok)
! 			return InvalidOid;
! 		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 	}
  	else if (clist->next != NULL)
! 	{
! 		if (missing_ok)
! 			return InvalidOid;
! 		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one function named \"%s\"",
! 							pro_name_or_oid)));
! 	}
  
  	result = clist->oid;
  
! 	return result;
  }
  
  /*
*************** regprocedurein(PG_FUNCTION_ARGS)
*** 263,269 ****
  		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(pro_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
--- 316,322 ----
  		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(pro_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
*************** Datum
*** 431,443 ****
  regoperin(PG_FUNCTION_ARGS)
  {
  	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
  	Oid			result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '0' ? */
  	if (strcmp(opr_name_or_oid, "0") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (opr_name_or_oid[0] >= '0' &&
--- 484,526 ----
  regoperin(PG_FUNCTION_ARGS)
  {
  	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regoper_guts(opr_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regoper		- converts "oprname" to operator OID
+  *
+  * Diffrence from regoper is, this does not throw an error if the operator
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regoper(PG_FUNCTION_ARGS)
+ {
+ 	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regoper_guts(opr_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * Guts of regoperin and to_regoper.
+  * If missing_ok is true, returns InvalidOid when the operator does not exist.
+  */
+ static Oid
+ regoper_guts(char *opr_name_or_oid, bool missing_ok)
+ {
  	Oid			result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '0' ? */
  	if (strcmp(opr_name_or_oid, "0") == 0)
! 		return InvalidOid;
  
  	/* Numeric OID? */
  	if (opr_name_or_oid[0] >= '0' &&
*************** regoperin(PG_FUNCTION_ARGS)
*** 445,452 ****
  		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(opr_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a name, possibly schema-qualified */
--- 528,535 ----
  		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(opr_name_or_oid)));
! 		return result;
  	}
  
  	/* Else it's a name, possibly schema-qualified */
*************** regoperin(PG_FUNCTION_ARGS)
*** 485,500 ****
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("operator does not exist: %s", opr_name_or_oid)));
  		else if (matches > 1)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one operator named %s",
! 							opr_name_or_oid)));
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 568,593 ----
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 		{
! 			if (missing_ok)
! 				return InvalidOid;
! 			else
! 				ereport(ERROR,
! 						(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 						 errmsg("operator does not exist: %s", opr_name_or_oid)));
! 		}
  		else if (matches > 1)
! 		{
! 			if (missing_ok)
! 				return InvalidOid;
! 			else
! 				ereport(ERROR,
! 						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 						 errmsg("more than one operator named %s",
! 								opr_name_or_oid)));
! 		}
  
! 		return result;
  	}
  
  	/*
*************** regoperin(PG_FUNCTION_ARGS)
*** 502,522 ****
  	 * pg_operator entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(opr_name_or_oid);
! 	clist = OpernameGetCandidates(names, '\0');
  
  	if (clist == NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("operator does not exist: %s", opr_name_or_oid)));
  	else if (clist->next != NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 				 errmsg("more than one operator named %s",
! 						opr_name_or_oid)));
  
  	result = clist->oid;
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 595,625 ----
  	 * pg_operator entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(opr_name_or_oid);
! 	clist = OpernameGetCandidates(names, '\0', missing_ok);
  
  	if (clist == NULL)
! 	{
! 		if (missing_ok)
! 			return InvalidOid;
! 		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("operator does not exist: %s", opr_name_or_oid)));
! 	}
  	else if (clist->next != NULL)
! 	{
! 		if (missing_ok)
! 			return InvalidOid;
! 		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one operator named %s",
! 							opr_name_or_oid)));
! 	}
  
  	result = clist->oid;
  
! 	return result;
  }
  
  /*
*************** regoperout(PG_FUNCTION_ARGS)
*** 558,564 ****
  			 * qualify it.
  			 */
  			clist = OpernameGetCandidates(list_make1(makeString(oprname)),
! 										  '\0');
  			if (clist != NULL && clist->next == NULL &&
  				clist->oid == oprid)
  				result = pstrdup(oprname);
--- 661,667 ----
  			 * qualify it.
  			 */
  			clist = OpernameGetCandidates(list_make1(makeString(oprname)),
! 										  '\0', false);
  			if (clist != NULL && clist->next == NULL &&
  				clist->oid == oprid)
  				result = pstrdup(oprname);
*************** Datum
*** 804,815 ****
  regclassin(PG_FUNCTION_ARGS)
  {
  	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
  	Oid			result = InvalidOid;
  	List	   *names;
  
  	/* '-' ? */
  	if (strcmp(class_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (class_name_or_oid[0] >= '0' &&
--- 907,948 ----
  regclassin(PG_FUNCTION_ARGS)
  {
  	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regclass_guts(class_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regclass		- converts "classname" to class OID
+  *
+  * Diffrence from regclassin is, this does not throw an error if the classname
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regclass(PG_FUNCTION_ARGS)
+ {
+ 	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regclass_guts(class_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * Guts of regclassin and to_regclass.
+  * If missing_ok is true, returns InvalidOid when the classname does not exist.
+  */
+ static Oid
+ regclass_guts(char *class_name_or_oid, bool missing_ok)
+ {
  	Oid			result = InvalidOid;
  	List	   *names;
  
  	/* '-' ? */
  	if (strcmp(class_name_or_oid, "-") == 0)
! 		return result;
  
  	/* Numeric OID? */
  	if (class_name_or_oid[0] >= '0' &&
*************** regclassin(PG_FUNCTION_ARGS)
*** 817,824 ****
  		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										CStringGetDatum(class_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a name, possibly schema-qualified */
--- 950,957 ----
  		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(class_name_or_oid)));
! 		return result;
  	}
  
  	/* Else it's a name, possibly schema-qualified */
*************** regclassin(PG_FUNCTION_ARGS)
*** 848,863 ****
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
  		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_TABLE),
! 			   errmsg("relation \"%s\" does not exist", class_name_or_oid)));
  
  		/* We assume there can be only one match */
  
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 981,999 ----
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
  		else
! 			if (missing_ok)
! 				return InvalidOid;
! 			else
! 				ereport(ERROR,
! 						(errcode(ERRCODE_UNDEFINED_TABLE),
! 						 errmsg("relation \"%s\" does not exist", class_name_or_oid)));
  
  		/* We assume there can be only one match */
  
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		return result;
  	}
  
  	/*
*************** regclassin(PG_FUNCTION_ARGS)
*** 865,875 ****
  	 * pg_class entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(class_name_or_oid);
  
  	/* We might not even have permissions on this relation; don't lock it. */
! 	result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, false);
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 1001,1013 ----
  	 * pg_class entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(class_name_or_oid);
+ 	if (names == NIL)
+ 		return InvalidOid;
  
  	/* We might not even have permissions on this relation; don't lock it. */
! 	result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, missing_ok);
  
! 	return result;
  }
  
  /*
*************** Datum
*** 968,979 ****
  regtypein(PG_FUNCTION_ARGS)
  {
  	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
  	Oid			result = InvalidOid;
  	int32		typmod;
  
  	/* '-' ? */
  	if (strcmp(typ_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (typ_name_or_oid[0] >= '0' &&
--- 1106,1147 ----
  regtypein(PG_FUNCTION_ARGS)
  {
  	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regtype_guts(typ_name_or_oid, false);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * to_regtype		- converts "typename" to type OID
+  *
+  * Diffrence from regtypein is, this does not throw an error if the typename
+  * does not exist.
+  * Note: this is not an I/O function.
+  */
+ Datum
+ to_regtype(PG_FUNCTION_ARGS)
+ {
+ 	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 
+ 	result = regtype_guts(typ_name_or_oid, true);
+ 	PG_RETURN_OID(result);
+ }
+ 
+ /*
+  * Guts of regtypein and to_regtype.
+  * If missing_ok is true, returns InvalidOid when the typename does not exist.
+  */
+ static Oid
+ regtype_guts(char *typ_name_or_oid, bool missing_ok)
+ {
  	Oid			result = InvalidOid;
  	int32		typmod;
  
  	/* '-' ? */
  	if (strcmp(typ_name_or_oid, "-") == 0)
! 		return InvalidOid;
  
  	/* Numeric OID? */
  	if (typ_name_or_oid[0] >= '0' &&
*************** regtypein(PG_FUNCTION_ARGS)
*** 981,988 ****
  		strspn(typ_name_or_oid, "0123456789") == strlen(typ_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(typ_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a type name, possibly schema-qualified or decorated */
--- 1149,1156 ----
  		strspn(typ_name_or_oid, "0123456789") == strlen(typ_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(typ_name_or_oid)));
! 		return result;
  	}
  
  	/* Else it's a type name, possibly schema-qualified or decorated */
*************** regtypein(PG_FUNCTION_ARGS)
*** 1011,1017 ****
  
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
! 		else
  			ereport(ERROR,
  					(errcode(ERRCODE_UNDEFINED_OBJECT),
  					 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
--- 1179,1185 ----
  
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  			result = HeapTupleGetOid(tuple);
! 		else if (!missing_ok)
  			ereport(ERROR,
  					(errcode(ERRCODE_UNDEFINED_OBJECT),
  					 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
*************** regtypein(PG_FUNCTION_ARGS)
*** 1021,1036 ****
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
  	 * Normal case: invoke the full parser to deal with special cases such as
  	 * array syntax.
  	 */
! 	parseTypeString(typ_name_or_oid, &result, &typmod);
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 1189,1204 ----
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		return result;
  	}
  
  	/*
  	 * Normal case: invoke the full parser to deal with special cases such as
  	 * array syntax.
  	 */
! 	parseTypeString(typ_name_or_oid, &result, &typmod, missing_ok);
  
! 	return result;
  }
  
  /*
*************** regconfigin(PG_FUNCTION_ARGS)
*** 1130,1136 ****
  		strspn(cfg_name_or_oid, "0123456789") == strlen(cfg_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(cfg_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
--- 1298,1304 ----
  		strspn(cfg_name_or_oid, "0123456789") == strlen(cfg_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(cfg_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
*************** regdictionaryin(PG_FUNCTION_ARGS)
*** 1240,1246 ****
  		strspn(dict_name_or_oid, "0123456789") == strlen(dict_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										 CStringGetDatum(dict_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
--- 1408,1414 ----
  		strspn(dict_name_or_oid, "0123456789") == strlen(dict_name_or_oid))
  	{
  		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 								  CStringGetDatum(dict_name_or_oid)));
  		PG_RETURN_OID(result);
  	}
  
*************** parseNameAndArgTypes(const char *string,
*** 1523,1529 ****
  		else
  		{
  			/* Use full parser to resolve the type name */
! 			parseTypeString(typename, &typeid, &typmod);
  		}
  		if (*nargs >= FUNC_MAX_ARGS)
  			ereport(ERROR,
--- 1691,1697 ----
  		else
  		{
  			/* Use full parser to resolve the type name */
! 			parseTypeString(typename, &typeid, &typmod, false);
  		}
  		if (*nargs >= FUNC_MAX_ARGS)
  			ereport(ERROR,
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
new file mode 100644
index a9b9794..f1d698e
*** a/src/backend/utils/misc/guc.c
--- b/src/backend/utils/misc/guc.c
*************** flatten_set_variable_args(const char *na
*** 6454,6460 ****
  					Datum		interval;
  					char	   *intervalout;
  
! 					typenameTypeIdAndMod(NULL, typeName, &typoid, &typmod);
  					Assert(typoid == INTERVALOID);
  
  					interval =
--- 6454,6460 ----
  					Datum		interval;
  					char	   *intervalout;
  
! 					typenameTypeIdAndMod(NULL, typeName, &typoid, &typmod, false);
  					Assert(typoid == INTERVALOID);
  
  					interval =
diff --git a/src/include/catalog/namespace.h b/src/include/catalog/namespace.h
new file mode 100644
index b30e5e8..350fafe
*** a/src/include/catalog/namespace.h
--- b/src/include/catalog/namespace.h
*************** extern FuncCandidateList FuncnameGetCand
*** 76,82 ****
  extern bool FunctionIsVisible(Oid funcid);
  
  extern Oid	OpernameGetOprid(List *names, Oid oprleft, Oid oprright);
! extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind);
  extern bool OperatorIsVisible(Oid oprid);
  
  extern Oid	OpclassnameGetOpcid(Oid amid, const char *opcname);
--- 76,83 ----
  extern bool FunctionIsVisible(Oid funcid);
  
  extern Oid	OpernameGetOprid(List *names, Oid oprleft, Oid oprright);
! extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind,
! 					  bool missing_ok);
  extern bool OperatorIsVisible(Oid oprid);
  
  extern Oid	OpclassnameGetOpcid(Oid amid, const char *opcname);
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
new file mode 100644
index 9fc61eb..c89d593
*** a/src/include/catalog/pg_proc.h
--- b/src/include/catalog/pg_proc.h
*************** DATA(insert OID =  44 (  regprocin		   P
*** 173,178 ****
--- 173,180 ----
  DESCR("I/O");
  DATA(insert OID =  45 (  regprocout		   PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "24" _null_ _null_ _null_ _null_ regprocout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3208 (  to_regproc		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 24 "2275" _null_ _null_ _null_ _null_ to_regproc _null_ _null_ _null_ ));
+ DESCR("convert proname to regproc");
  DATA(insert OID =  46 (  textin			   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 25 "2275" _null_ _null_ _null_ _null_ textin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID =  47 (  textout		   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2275 "25" _null_ _null_ _null_ _null_ textout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2214 (  regoperin			PG
*** 3300,3305 ****
--- 3302,3309 ----
  DESCR("I/O");
  DATA(insert OID = 2215 (  regoperout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2203" _null_ _null_ _null_ _null_ regoperout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3206 (  to_regoper		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2203 "2275" _null_ _null_ _null_ _null_ to_regoper _null_ _null_ _null_ ));
+ DESCR("convert operator name to regoper");
  DATA(insert OID = 2216 (  regoperatorin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2204 "2275" _null_ _null_ _null_ _null_ regoperatorin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2217 (  regoperatorout	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2204" _null_ _null_ _null_ _null_ regoperatorout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2218 (  regclassin		PG
*** 3308,3317 ****
--- 3312,3325 ----
  DESCR("I/O");
  DATA(insert OID = 2219 (  regclassout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2205" _null_ _null_ _null_ _null_ regclassout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3209 (  to_regclass		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "2275" _null_ _null_ _null_ _null_ to_regclass _null_ _null_ _null_ ));
+ DESCR("convert classname to regclass");
  DATA(insert OID = 2220 (  regtypein			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ regtypein _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2221 (  regtypeout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2206" _null_ _null_ _null_ _null_ regtypeout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3207 (  to_regtype		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ to_regtype _null_ _null_ _null_ ));
+ DESCR("convert type name to regtype");
  DATA(insert OID = 1079 (  regclass			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "25" _null_ _null_ _null_ _null_	text_regclass _null_ _null_ _null_ ));
  DESCR("convert text to regclass");
  
diff --git a/src/include/parser/parse_type.h b/src/include/parser/parse_type.h
new file mode 100644
index ab73148..b45538a
*** a/src/include/parser/parse_type.h
--- b/src/include/parser/parse_type.h
*************** extern Type typenameType(ParseState *pst
*** 27,33 ****
  			 int32 *typmod_p);
  extern Oid	typenameTypeId(ParseState *pstate, const TypeName *typeName);
  extern void typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName,
! 					 Oid *typeid_p, int32 *typmod_p);
  
  extern char *TypeNameToString(const TypeName *typeName);
  extern char *TypeNameListToString(List *typenames);
--- 27,33 ----
  			 int32 *typmod_p);
  extern Oid	typenameTypeId(ParseState *pstate, const TypeName *typeName);
  extern void typenameTypeIdAndMod(ParseState *pstate, const TypeName *typeName,
! 					 Oid *typeid_p, int32 *typmod_p, bool missing_ok);
  
  extern char *TypeNameToString(const TypeName *typeName);
  extern char *TypeNameListToString(List *typenames);
*************** extern Datum stringTypeDatum(Type tp, ch
*** 47,53 ****
  
  extern Oid	typeidTypeRelid(Oid type_id);
  
! extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p);
  
  #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
  
--- 47,53 ----
  
  extern Oid	typeidTypeRelid(Oid type_id);
  
! extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p, bool missing_ok);
  
  #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
  
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
new file mode 100644
index b90d88d..85dee8a
*** a/src/include/utils/builtins.h
--- b/src/include/utils/builtins.h
*************** extern char *regexp_fixed_prefix(text *t
*** 597,602 ****
--- 597,603 ----
  /* regproc.c */
  extern Datum regprocin(PG_FUNCTION_ARGS);
  extern Datum regprocout(PG_FUNCTION_ARGS);
+ extern Datum to_regproc(PG_FUNCTION_ARGS);
  extern Datum regprocrecv(PG_FUNCTION_ARGS);
  extern Datum regprocsend(PG_FUNCTION_ARGS);
  extern Datum regprocedurein(PG_FUNCTION_ARGS);
*************** extern Datum regoperin(PG_FUNCTION_ARGS)
*** 607,612 ****
--- 608,614 ----
  extern Datum regoperout(PG_FUNCTION_ARGS);
  extern Datum regoperrecv(PG_FUNCTION_ARGS);
  extern Datum regopersend(PG_FUNCTION_ARGS);
+ extern Datum to_regoper(PG_FUNCTION_ARGS);
  extern Datum regoperatorin(PG_FUNCTION_ARGS);
  extern Datum regoperatorout(PG_FUNCTION_ARGS);
  extern Datum regoperatorrecv(PG_FUNCTION_ARGS);
*************** extern Datum regclassin(PG_FUNCTION_ARGS
*** 615,624 ****
--- 617,628 ----
  extern Datum regclassout(PG_FUNCTION_ARGS);
  extern Datum regclassrecv(PG_FUNCTION_ARGS);
  extern Datum regclasssend(PG_FUNCTION_ARGS);
+ extern Datum to_regclass(PG_FUNCTION_ARGS);
  extern Datum regtypein(PG_FUNCTION_ARGS);
  extern Datum regtypeout(PG_FUNCTION_ARGS);
  extern Datum regtyperecv(PG_FUNCTION_ARGS);
  extern Datum regtypesend(PG_FUNCTION_ARGS);
+ extern Datum to_regtype(PG_FUNCTION_ARGS);
  extern Datum regconfigin(PG_FUNCTION_ARGS);
  extern Datum regconfigout(PG_FUNCTION_ARGS);
  extern Datum regconfigrecv(PG_FUNCTION_ARGS);
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
new file mode 100644
index a81c185..5a92ee0
*** a/src/pl/plperl/plperl.c
--- b/src/pl/plperl/plperl.c
*************** plperl_spi_prepare(char *query, int argc
*** 3401,3407 ****
  			char	   *typstr;
  
  			typstr = sv2cstr(argv[i]);
! 			parseTypeString(typstr, &typId, &typmod);
  			pfree(typstr);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
--- 3401,3407 ----
  			char	   *typstr;
  
  			typstr = sv2cstr(argv[i]);
! 			parseTypeString(typstr, &typId, &typmod, false);
  			pfree(typstr);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
new file mode 100644
index c0cb585..1862293
*** a/src/pl/plpgsql/src/pl_gram.y
--- b/src/pl/plpgsql/src/pl_gram.y
*************** parse_datatype(const char *string, int l
*** 3462,3468 ****
  	error_context_stack = &syntax_errcontext;
  
  	/* Let the main parser try to parse it under standard SQL rules */
! 	parseTypeString(string, &type_id, &typmod);
  
  	/* Restore former ereport callback */
  	error_context_stack = syntax_errcontext.previous;
--- 3462,3468 ----
  	error_context_stack = &syntax_errcontext;
  
  	/* Let the main parser try to parse it under standard SQL rules */
! 	parseTypeString(string, &type_id, &typmod, false);
  
  	/* Restore former ereport callback */
  	error_context_stack = syntax_errcontext.previous;
diff --git a/src/pl/plpython/plpy_spi.c b/src/pl/plpython/plpy_spi.c
new file mode 100644
index 982bf84..060d514
*** a/src/pl/plpython/plpy_spi.c
--- b/src/pl/plpython/plpy_spi.c
*************** PLy_spi_prepare(PyObject *self, PyObject
*** 113,119 ****
  			 *information for input conversion.
  			 ********************************************************/
  
! 			parseTypeString(sptr, &typeId, &typmod);
  
  			typeTup = SearchSysCache1(TYPEOID,
  									  ObjectIdGetDatum(typeId));
--- 113,119 ----
  			 *information for input conversion.
  			 ********************************************************/
  
! 			parseTypeString(sptr, &typeId, &typmod, false);
  
  			typeTup = SearchSysCache1(TYPEOID,
  									  ObjectIdGetDatum(typeId));
diff --git a/src/pl/tcl/pltcl.c b/src/pl/tcl/pltcl.c
new file mode 100644
index 0538038..c89ee7a
*** a/src/pl/tcl/pltcl.c
--- b/src/pl/tcl/pltcl.c
*************** pltcl_SPI_prepare(ClientData cdata, Tcl_
*** 2161,2167 ****
  						typIOParam;
  			int32		typmod;
  
! 			parseTypeString(args[i], &typId, &typmod);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
  
--- 2161,2167 ----
  						typIOParam;
  			int32		typmod;
  
! 			parseTypeString(args[i], &typId, &typmod, false);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
  
diff --git a/src/test/regress/expected/regproc.out b/src/test/regress/expected/regproc.out
new file mode 100644
index ...80a1e29
*** a/src/test/regress/expected/regproc.out
--- b/src/test/regress/expected/regproc.out
***************
*** 0 ****
--- 1,188 ----
+ --
+ -- regproc
+ --
+ /* Objects exist, ok. */
+ -- without schemaname
+ SELECT regoper('||/');
+  regoper 
+ ---------
+  ||/
+ (1 row)
+ 
+ SELECT regproc('now');
+  regproc 
+ ---------
+  now
+ (1 row)
+ 
+ SELECT regclass('pg_class');
+  regclass 
+ ----------
+  pg_class
+ (1 row)
+ 
+ SELECT regtype('integer');
+  regtype 
+ ---------
+  integer
+ (1 row)
+ 
+ SELECT to_regoper('||/');
+  to_regoper 
+ ------------
+  ||/
+ (1 row)
+ 
+ SELECT to_regproc('now');
+  to_regproc 
+ ------------
+  now
+ (1 row)
+ 
+ SELECT to_regclass('pg_class');
+  to_regclass 
+ -------------
+  pg_class
+ (1 row)
+ 
+ SELECT to_regtype('int4');
+  to_regtype 
+ ------------
+  integer
+ (1 row)
+ 
+ -- with schemaname
+ SELECT regoper('pg_catalog.||/');
+  regoper 
+ ---------
+  ||/
+ (1 row)
+ 
+ SELECT regproc('pg_catalog.now');
+  regproc 
+ ---------
+  now
+ (1 row)
+ 
+ SELECT regclass('pg_catalog.pg_class');
+  regclass 
+ ----------
+  pg_class
+ (1 row)
+ 
+ SELECT regtype('pg_catalog.int4');
+  regtype 
+ ---------
+  integer
+ (1 row)
+ 
+ SELECT to_regoper('pg_catalog.||/');
+  to_regoper 
+ ------------
+  ||/
+ (1 row)
+ 
+ SELECT to_regproc('pg_catalog.now');
+  to_regproc 
+ ------------
+  now
+ (1 row)
+ 
+ SELECT to_regclass('pg_catalog.pg_class');
+  to_regclass 
+ -------------
+  pg_class
+ (1 row)
+ 
+ SELECT to_regtype('pg_catalog.int4');
+  to_regtype 
+ ------------
+  integer
+ (1 row)
+ 
+ /* Objects don't exist, error. */
+ -- without schemaname
+ SELECT regoper('||//');
+ ERROR:  operator does not exist: ||//
+ LINE 3: SELECT regoper('||//');
+                        ^
+ SELECT regproc('know');
+ ERROR:  function "know" does not exist
+ LINE 1: SELECT regproc('know');
+                        ^
+ SELECT regclass('pg_classes');
+ ERROR:  relation "pg_classes" does not exist
+ LINE 1: SELECT regclass('pg_classes');
+                         ^
+ SELECT regtype('int3');
+ ERROR:  type "int3" does not exist
+ LINE 1: SELECT regtype('int3');
+                        ^
+ -- with schemaname
+ SELECT regoper('ng_catalog.||/');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regoper('ng_catalog.||/');
+                        ^
+ SELECT regproc('ng_catalog.now');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regproc('ng_catalog.now');
+                        ^
+ SELECT regclass('ng_catalog.pg_class');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regclass('ng_catalog.pg_class');
+                         ^
+ SELECT regtype('ng_catalog.int4');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regtype('ng_catalog.int4');
+                        ^
+ /* Objects don't exist, but no error. */
+ -- without schemaname
+ SELECT to_regoper('||//');
+  to_regoper 
+ ------------
+  0
+ (1 row)
+ 
+ SELECT to_regproc('know');
+  to_regproc 
+ ------------
+  -
+ (1 row)
+ 
+ SELECT to_regclass('pg_classes');
+  to_regclass 
+ -------------
+  -
+ (1 row)
+ 
+ SELECT to_regtype('int3');
+  to_regtype 
+ ------------
+  -
+ (1 row)
+ 
+ -- with schemaname
+ SELECT to_regoper('ng_catalog.||/');
+  to_regoper 
+ ------------
+  0
+ (1 row)
+ 
+ SELECT to_regproc('ng_catalog.now');
+  to_regproc 
+ ------------
+  -
+ (1 row)
+ 
+ SELECT to_regclass('ng_catalog.pg_class');
+  to_regclass 
+ -------------
+  -
+ (1 row)
+ 
+ SELECT to_regtype('ng_catalog.int4');
+  to_regtype 
+ ------------
+  -
+ (1 row)
+ 
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
new file mode 100644
index 5758b07..36c1ece
*** a/src/test/regress/parallel_schedule
--- b/src/test/regress/parallel_schedule
*************** test: tablespace
*** 13,19 ****
  # ----------
  # The first group of parallel tests
  # ----------
! test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes
  
  # Depends on things setup during char, varchar and text
  test: strings
--- 13,19 ----
  # ----------
  # The first group of parallel tests
  # ----------
! test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes regproc
  
  # Depends on things setup during char, varchar and text
  test: strings
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
new file mode 100644
index 78348f5..9a54d7c
*** a/src/test/regress/serial_schedule
--- b/src/test/regress/serial_schedule
*************** test: uuid
*** 19,24 ****
--- 19,25 ----
  test: enum
  test: money
  test: rangetypes
+ test: regproc
  test: strings
  test: numerology
  test: point
diff --git a/src/test/regress/sql/regproc.sql b/src/test/regress/sql/regproc.sql
new file mode 100644
index ...2bbcea0
*** a/src/test/regress/sql/regproc.sql
--- b/src/test/regress/sql/regproc.sql
***************
*** 0 ****
--- 1,61 ----
+ --
+ -- regproc
+ --
+ 
+ /* Objects exist, ok. */
+ 
+ -- without schemaname
+ 
+ SELECT regoper('||/');
+ SELECT regproc('now');
+ SELECT regclass('pg_class');
+ SELECT regtype('integer');
+ 
+ SELECT to_regoper('||/');
+ SELECT to_regproc('now');
+ SELECT to_regclass('pg_class');
+ SELECT to_regtype('int4');
+ 
+ -- with schemaname
+ 
+ SELECT regoper('pg_catalog.||/');
+ SELECT regproc('pg_catalog.now');
+ SELECT regclass('pg_catalog.pg_class');
+ SELECT regtype('pg_catalog.int4');
+ 
+ SELECT to_regoper('pg_catalog.||/');
+ SELECT to_regproc('pg_catalog.now');
+ SELECT to_regclass('pg_catalog.pg_class');
+ SELECT to_regtype('pg_catalog.int4');
+ 
+ /* Objects don't exist, error. */
+ 
+ -- without schemaname
+ 
+ SELECT regoper('||//');
+ SELECT regproc('know');
+ SELECT regclass('pg_classes');
+ SELECT regtype('int3');
+ 
+ -- with schemaname
+ 
+ SELECT regoper('ng_catalog.||/');
+ SELECT regproc('ng_catalog.now');
+ SELECT regclass('ng_catalog.pg_class');
+ SELECT regtype('ng_catalog.int4');
+ 
+ /* Objects don't exist, but no error. */
+ 
+ -- without schemaname
+ 
+ SELECT to_regoper('||//');
+ SELECT to_regproc('know');
+ SELECT to_regclass('pg_classes');
+ SELECT to_regtype('int3');
+ 
+ -- with schemaname
+ 
+ SELECT to_regoper('ng_catalog.||/');
+ SELECT to_regproc('ng_catalog.now');
+ SELECT to_regclass('ng_catalog.pg_class');
+ SELECT to_regtype('ng_catalog.int4');

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
new file mode 100644
index ff50328..c76f4a4
*** a/doc/src/sgml/func.sgml
--- b/doc/src/sgml/func.sgml
*************** SELECT pg_type_is_visible('myschema.widg
*** 15040,15045 ****
--- 15040,15061 ----
      <primary>collation for</primary>
     </indexterm>
  
+    <indexterm>
+     <primary>to_regclass</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regproc</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regoper</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regtype</primary>
+    </indexterm>
+ 
    <para>
     <xref linkend="functions-info-catalog-table"> lists functions that
     extract information from the system catalogs.
*************** SELECT pg_type_is_visible('myschema.widg
*** 15210,15215 ****
--- 15226,15251 ----
         <entry><type>text</type></entry>
         <entry>get the collation of the argument</entry>
        </row>
+       <row>
+        <entry><literal><function>to_regclass(<parameter>table_name</parameter>)</function></literal></entry>
+        <entry><type>regclass</type></entry>
+        <entry>get the table oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regproc(<parameter>func_name</parameter>)</function></literal></entry>
+        <entry><type>regproc</type></entry>
+        <entry>get the function oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regoper(<parameter>operator_name</parameter>)</function></literal></entry>
+        <entry><type>regoper</type></entry>
+        <entry>get the operator oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regtype(<parameter>type_name</parameter>)</function></literal></entry>
+        <entry><type>regtype</type></entry>
+        <entry>get the type oid</entry>
+       </row>
       </tbody>
      </tgroup>
     </table>
*************** SELECT collation for ('foo' COLLATE "de_
*** 15375,15380 ****
--- 15411,15423 ----
    is not of a collatable data type, then an error is raised.
    </para>
  
+   <para>
+ 	to_regclass, to_regproc, to_regoper and to_regtype are functions
+ 	similar to the regclass, regproc, regoper and regtype casts, except
+ 	that they return NULL when the object is not found, instead of raising
+ 	an error.
+   </para>
+ 
     <indexterm>
      <primary>col_description</primary>
     </indexterm>
diff --git a/src/backend/catalog/namespace.c b/src/backend/catalog/namespace.c
new file mode 100644
index 6c2a5d2..112a826
*** a/src/backend/catalog/namespace.c
--- b/src/backend/catalog/namespace.c
*************** OpernameGetOprid(List *names, Oid oprlef
*** 1556,1562 ****
   * will be InvalidOid for a prefix or postfix oprkind.	nargs is 2, too.
   */
  FuncCandidateList
! OpernameGetCandidates(List *names, char oprkind)
  {
  	FuncCandidateList resultList = NULL;
  	char	   *resultSpace = NULL;
--- 1556,1562 ----
   * will be InvalidOid for a prefix or postfix oprkind.	nargs is 2, too.
   */
  FuncCandidateList
! OpernameGetCandidates(List *names, char oprkind, bool missing_schema_ok)
  {
  	FuncCandidateList resultList = NULL;
  	char	   *resultSpace = NULL;
*************** OpernameGetCandidates(List *names, char 
*** 1573,1579 ****
  	if (schemaname)
  	{
  		/* use exact schema given */
! 		namespaceId = LookupExplicitNamespace(schemaname, false);
  	}
  	else
  	{
--- 1573,1581 ----
  	if (schemaname)
  	{
  		/* use exact schema given */
! 		namespaceId = LookupExplicitNamespace(schemaname, missing_schema_ok);
! 		if (!OidIsValid(namespaceId))
! 			return NULL;
  	}
  	else
  	{
diff --git a/src/backend/parser/parse_oper.c b/src/backend/parser/parse_oper.c
new file mode 100644
index 99dbd30..a2b712d
*** a/src/backend/parser/parse_oper.c
--- b/src/backend/parser/parse_oper.c
*************** oper(ParseState *pstate, List *opname, O
*** 407,413 ****
  		FuncCandidateList clist;
  
  		/* Get binary operators of given name */
! 		clist = OpernameGetCandidates(opname, 'b');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 407,413 ----
  		FuncCandidateList clist;
  
  		/* Get binary operators of given name */
! 		clist = OpernameGetCandidates(opname, 'b', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
*************** right_oper(ParseState *pstate, List *op,
*** 553,559 ****
  		FuncCandidateList clist;
  
  		/* Get postfix operators of given name */
! 		clist = OpernameGetCandidates(op, 'r');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 553,559 ----
  		FuncCandidateList clist;
  
  		/* Get postfix operators of given name */
! 		clist = OpernameGetCandidates(op, 'r', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
*************** left_oper(ParseState *pstate, List *op, 
*** 631,637 ****
  		FuncCandidateList clist;
  
  		/* Get prefix operators of given name */
! 		clist = OpernameGetCandidates(op, 'l');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 631,637 ----
  		FuncCandidateList clist;
  
  		/* Get prefix operators of given name */
! 		clist = OpernameGetCandidates(op, 'l', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
new file mode 100644
index b329dfb..d27b969
*** a/src/backend/parser/parse_type.c
--- b/src/backend/parser/parse_type.c
*************** pts_error_callback(void *arg)
*** 706,714 ****
   * Given a string that is supposed to be a SQL-compatible type declaration,
   * such as "int4" or "integer" or "character varying(32)", parse
   * the string and convert it to a type OID and type modifier.
   */
  void
! parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p)
  {
  	StringInfoData buf;
  	List	   *raw_parsetree_list;
--- 706,716 ----
   * Given a string that is supposed to be a SQL-compatible type declaration,
   * such as "int4" or "integer" or "character varying(32)", parse
   * the string and convert it to a type OID and type modifier.
+  * If the type name is not found, return InvalidOid if missing_ok
+  * = true, otherwise raise an error.
   */
  void
! parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p, bool missing_ok)
  {
  	StringInfoData buf;
  	List	   *raw_parsetree_list;
*************** parseTypeString(const char *str, Oid *ty
*** 717,722 ****
--- 719,725 ----
  	TypeCast   *typecast;
  	TypeName   *typeName;
  	ErrorContextCallback ptserrcontext;
+ 	Type		tup;
  
  	/* make sure we give useful error for empty input */
  	if (strspn(str, " \t\n\r\f") == strlen(str))
*************** parseTypeString(const char *str, Oid *ty
*** 782,788 ****
  	if (typeName->setof)
  		goto fail;
  
! 	typenameTypeIdAndMod(NULL, typeName, typeid_p, typmod_p);
  
  	pfree(buf.data);
  
--- 785,818 ----
  	if (typeName->setof)
  		goto fail;
  
! 	tup = LookupTypeName(NULL, typeName, typmod_p, missing_ok);
! 
! 	if (!missing_ok)
! 	{
! 		if (tup == NULL)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_OBJECT),
! 					errmsg("type \"%s\" does not exist",
! 							TypeNameToString(typeName)),
! 					parser_errposition(NULL, typeName->location)));
! 		if (!((Form_pg_type) GETSTRUCT(tup))->typisdefined)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_OBJECT),
! 					errmsg("type \"%s\" is only a shell",
! 							TypeNameToString(typeName)),
! 					parser_errposition(NULL, typeName->location)));
! 		*typeid_p = HeapTupleGetOid(tup);
! 	}
! 	else
! 	{
! 		if (tup == NULL || !((Form_pg_type) GETSTRUCT(tup))->typisdefined)
! 			*typeid_p = InvalidOid;
! 		else
! 			*typeid_p = HeapTupleGetOid(tup);
! 	}
! 
! 	if (tup)
! 		ReleaseSysCache(tup);
  
  	pfree(buf.data);
  
diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
new file mode 100644
index 5d73562..ea24edd
*** a/src/backend/utils/adt/regproc.c
--- b/src/backend/utils/adt/regproc.c
*************** static char *format_operator_internal(Oi
*** 45,50 ****
--- 45,54 ----
  static char *format_procedure_internal(Oid procedure_oid, bool force_qualify);
  static void parseNameAndArgTypes(const char *string, bool allowNone,
  					 List **names, int *nargs, Oid *argtypes);
+ static bool regoper_guts(char *opr_name_or_oid, RegProcedure *oprid_p, bool missing_ok);
+ static bool regproc_guts(char *pro_name_or_oid, Oid *proid_p, bool missing_ok);
+ static bool regclass_guts(char *class_name_or_oid, Oid *classid_p, bool missing_ok);
+ static bool regtype_guts(char *typ_name_or_oid, Oid *typid_p, bool missing_ok);
  
  
  /*****************************************************************************
*************** Datum
*** 63,84 ****
  regprocin(PG_FUNCTION_ARGS)
  {
  	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
! 	RegProcedure result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '-' ? */
  	if (strcmp(pro_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (pro_name_or_oid[0] >= '0' &&
  		pro_name_or_oid[0] <= '9' &&
  		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
  	{
! 		result = DatumGetObjectId(DirectFunctionCall1(oidin,
  										  CStringGetDatum(pro_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a name, possibly schema-qualified */
--- 67,122 ----
  regprocin(PG_FUNCTION_ARGS)
  {
  	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
! 	RegProcedure result;
! 
! 	regproc_guts(pro_name_or_oid, &result, false);
! 	PG_RETURN_OID(result);
! }
! 
! /*
!  * to_regproc	- converts "proname" to proc OID
!  *
!  * Diffrence from regprocin is, this does not throw an error and returns NULL
!  * if the proname does not exist.
!  * Note: this is not an I/O function.
!  */
! Datum
! to_regproc(PG_FUNCTION_ARGS)
! {
! 	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
! 	RegProcedure result;
! 
! 	if (regproc_guts(pro_name_or_oid, &result, true))
! 		PG_RETURN_OID(result);
! 	else
! 		PG_RETURN_NULL();
! }
! 
! /*
!  * Guts of regoperin and to_regproc.
!  * If the proname is found, returns true and the OID is stored into *proid_p.
!  * If not found and missing_ok is true, returns false instead of raising an error.
!  */
! static bool
! regproc_guts(char *pro_name_or_oid, RegProcedure *proid_p, bool missing_ok)
! {
  	List	   *names;
  	FuncCandidateList clist;
  
+ 	*proid_p = InvalidOid;
+ 
  	/* '-' ? */
  	if (strcmp(pro_name_or_oid, "-") == 0)
! 		return true;
  
  	/* Numeric OID? */
  	if (pro_name_or_oid[0] >= '0' &&
  		pro_name_or_oid[0] <= '9' &&
  		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
  	{
! 		*proid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
  										  CStringGetDatum(pro_name_or_oid)));
! 		return true;
  	}
  
  	/* Else it's a name, possibly schema-qualified */
*************** regprocin(PG_FUNCTION_ARGS)
*** 108,114 ****
  
  		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  		{
! 			result = (RegProcedure) HeapTupleGetOid(tuple);
  			if (++matches > 1)
  				break;
  		}
--- 146,152 ----
  
  		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  		{
! 			*proid_p = (RegProcedure) HeapTupleGetOid(tuple);
  			if (++matches > 1)
  				break;
  		}
*************** regprocin(PG_FUNCTION_ARGS)
*** 117,133 ****
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 
  		else if (matches > 1)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one function named \"%s\"",
! 							pro_name_or_oid)));
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 155,178 ----
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 		{
! 			if (!missing_ok)
! 				ereport(ERROR,
! 						(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 						 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 			return false;
! 		}
  		else if (matches > 1)
! 		{
! 			if (!missing_ok)
! 				ereport(ERROR,
! 						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 						 errmsg("more than one function named \"%s\"",
! 								pro_name_or_oid)));
! 			return false;
! 		}
  
! 		return true;
  	}
  
  	/*
*************** regprocin(PG_FUNCTION_ARGS)
*** 135,155 ****
  	 * pg_proc entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(pro_name_or_oid);
! 	clist = FuncnameGetCandidates(names, -1, NIL, false, false, false);
  
  	if (clist == NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
  	else if (clist->next != NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 				 errmsg("more than one function named \"%s\"",
! 						pro_name_or_oid)));
  
! 	result = clist->oid;
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 180,208 ----
  	 * pg_proc entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(pro_name_or_oid);
! 	clist = FuncnameGetCandidates(names, -1, NIL, false, false, missing_ok);
  
  	if (clist == NULL)
! 	{
! 		if (!missing_ok)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 		return false;
! 	}
  	else if (clist->next != NULL)
! 	{
! 		if (!missing_ok)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one function named \"%s\"",
! 							pro_name_or_oid)));
! 		return false;
! 	}
  
! 	*proid_p = clist->oid;
  
! 	return true;
  }
  
  /*
*************** Datum
*** 431,452 ****
  regoperin(PG_FUNCTION_ARGS)
  {
  	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result = InvalidOid;
  	List	   *names;
  	FuncCandidateList clist;
  
  	/* '0' ? */
  	if (strcmp(opr_name_or_oid, "0") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (opr_name_or_oid[0] >= '0' &&
  		opr_name_or_oid[0] <= '9' &&
  		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
  	{
! 		result = DatumGetObjectId(DirectFunctionCall1(oidin,
  										  CStringGetDatum(opr_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a name, possibly schema-qualified */
--- 484,539 ----
  regoperin(PG_FUNCTION_ARGS)
  {
  	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result;
! 
! 	regoper_guts(opr_name_or_oid, &result, false);
! 	PG_RETURN_OID(result);
! }
! 
! /*
!  * to_regoper		- converts "oprname" to operator OID
!  *
!  * Diffrence from regoper is, this does not throw an error and returns NULL
!  * if the operator does not exist.
!  * Note: this is not an I/O function.
!  */
! Datum
! to_regoper(PG_FUNCTION_ARGS)
! {
! 	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result;
! 
! 	if (regoper_guts(opr_name_or_oid, &result, true))
! 		PG_RETURN_OID(result);
! 	else
! 		PG_RETURN_NULL();
! }
! 
! /*
!  * Guts of regoperin and to_regoper.
!  * If the operator is found, returns true and the OID is stored into *oprid_p.
!  * If not found and missing_ok is true, returns false instead of raising an error.
!  */
! static bool
! regoper_guts(char *opr_name_or_oid, Oid *oprid_p, bool missing_ok)
! {
  	List	   *names;
  	FuncCandidateList clist;
  
+ 	*oprid_p = InvalidOid;
+ 
  	/* '0' ? */
  	if (strcmp(opr_name_or_oid, "0") == 0)
! 		return true;
  
  	/* Numeric OID? */
  	if (opr_name_or_oid[0] >= '0' &&
  		opr_name_or_oid[0] <= '9' &&
  		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
  	{
! 		*oprid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
  										  CStringGetDatum(opr_name_or_oid)));
! 		return true;
  	}
  
  	/* Else it's a name, possibly schema-qualified */
*************** regoperin(PG_FUNCTION_ARGS)
*** 476,482 ****
  
  		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  		{
! 			result = HeapTupleGetOid(tuple);
  			if (++matches > 1)
  				break;
  		}
--- 563,569 ----
  
  		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
  		{
! 			*oprid_p = HeapTupleGetOid(tuple);
  			if (++matches > 1)
  				break;
  		}
*************** regoperin(PG_FUNCTION_ARGS)
*** 485,500 ****
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("operator does not exist: %s", opr_name_or_oid)));
  		else if (matches > 1)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one operator named %s",
! 							opr_name_or_oid)));
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 572,595 ----
  		heap_close(hdesc, AccessShareLock);
  
  		if (matches == 0)
! 		{
! 			if (!missing_ok)
! 				ereport(ERROR,
! 						(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 						 errmsg("operator does not exist: %s", opr_name_or_oid)));
! 			return false;
! 		}
  		else if (matches > 1)
! 		{
! 			if (!missing_ok)
! 				ereport(ERROR,
! 						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 						 errmsg("more than one operator named %s",
! 								opr_name_or_oid)));
! 			return false;
! 		}
  
! 		return true;
  	}
  
  	/*
*************** regoperin(PG_FUNCTION_ARGS)
*** 502,522 ****
  	 * pg_operator entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(opr_name_or_oid);
! 	clist = OpernameGetCandidates(names, '\0');
  
  	if (clist == NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("operator does not exist: %s", opr_name_or_oid)));
  	else if (clist->next != NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 				 errmsg("more than one operator named %s",
! 						opr_name_or_oid)));
  
! 	result = clist->oid;
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 597,625 ----
  	 * pg_operator entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(opr_name_or_oid);
! 	clist = OpernameGetCandidates(names, '\0', missing_ok);
  
  	if (clist == NULL)
! 	{
! 		if (!missing_ok)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("operator does not exist: %s", opr_name_or_oid)));
! 		return false;
! 	}
  	else if (clist->next != NULL)
! 	{
! 		if (!missing_ok)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one operator named %s",
! 							opr_name_or_oid)));
! 		return false;
! 	}
  
! 	*oprid_p = clist->oid;
  
! 	return true;
  }
  
  /*
*************** regoperout(PG_FUNCTION_ARGS)
*** 558,564 ****
  			 * qualify it.
  			 */
  			clist = OpernameGetCandidates(list_make1(makeString(oprname)),
! 										  '\0');
  			if (clist != NULL && clist->next == NULL &&
  				clist->oid == oprid)
  				result = pstrdup(oprname);
--- 661,667 ----
  			 * qualify it.
  			 */
  			clist = OpernameGetCandidates(list_make1(makeString(oprname)),
! 										  '\0', false);
  			if (clist != NULL && clist->next == NULL &&
  				clist->oid == oprid)
  				result = pstrdup(oprname);
*************** Datum
*** 804,824 ****
  regclassin(PG_FUNCTION_ARGS)
  {
  	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result = InvalidOid;
  	List	   *names;
  
  	/* '-' ? */
  	if (strcmp(class_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (class_name_or_oid[0] >= '0' &&
  		class_name_or_oid[0] <= '9' &&
  		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
  	{
! 		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										CStringGetDatum(class_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a name, possibly schema-qualified */
--- 907,966 ----
  regclassin(PG_FUNCTION_ARGS)
  {
  	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result;
! 
! 	if (!regclass_guts(class_name_or_oid, &result, false))
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_TABLE),
! 				 errmsg("relation \"%s\" does not exist", class_name_or_oid)));
! 
! 	PG_RETURN_OID(result);
! }
! 
! /*
!  * to_regclass		- converts "classname" to class OID
!  *
!  * Diffrence from regclassin is, this does not throw an error and return NULL
!  * if the classname does not exist.
!  * Note: this is not an I/O function.
!  */
! Datum
! to_regclass(PG_FUNCTION_ARGS)
! {
! 	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid		   result;
! 
! 	if (regclass_guts(class_name_or_oid, &result, true))
! 		PG_RETURN_OID(result);
! 	else
! 		PG_RETURN_NULL();
! }
! 
! /*
!  * Guts of regclassin and to_regclass.
!  * If the classname is found, returns true and the OID is stored into *classid_p.
!  * If not found and missing_ok is true, or in bootstrap mode, returns false instead
!  * of raising an error
!  */
! static bool
! regclass_guts(char *class_name_or_oid, Oid *classid_p, bool missing_ok)
! {
  	List	   *names;
  
+ 	*classid_p = InvalidOid;
+ 
  	/* '-' ? */
  	if (strcmp(class_name_or_oid, "-") == 0)
! 		return true;
  
  	/* Numeric OID? */
  	if (class_name_or_oid[0] >= '0' &&
  		class_name_or_oid[0] <= '9' &&
  		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
  	{
! 		*classid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(class_name_or_oid)));
! 		return true;
  	}
  
  	/* Else it's a name, possibly schema-qualified */
*************** regclassin(PG_FUNCTION_ARGS)
*** 846,863 ****
  									 NULL, 1, skey);
  
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
! 			result = HeapTupleGetOid(tuple);
  		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_TABLE),
! 			   errmsg("relation \"%s\" does not exist", class_name_or_oid)));
  
  		/* We assume there can be only one match */
  
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
--- 988,1003 ----
  									 NULL, 1, skey);
  
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
! 			*classid_p = HeapTupleGetOid(tuple);
  		else
! 			return false;
  
  		/* We assume there can be only one match */
  
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		return true;
  	}
  
  	/*
*************** regclassin(PG_FUNCTION_ARGS)
*** 867,875 ****
  	names = stringToQualifiedNameList(class_name_or_oid);
  
  	/* We might not even have permissions on this relation; don't lock it. */
! 	result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, false);
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 1007,1015 ----
  	names = stringToQualifiedNameList(class_name_or_oid);
  
  	/* We might not even have permissions on this relation; don't lock it. */
! 	*classid_p = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, missing_ok);
  
! 	return OidIsValid(*classid_p);
  }
  
  /*
*************** Datum
*** 968,988 ****
  regtypein(PG_FUNCTION_ARGS)
  {
  	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result = InvalidOid;
  	int32		typmod;
  
  	/* '-' ? */
  	if (strcmp(typ_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
  
  	/* Numeric OID? */
  	if (typ_name_or_oid[0] >= '0' &&
  		typ_name_or_oid[0] <= '9' &&
  		strspn(typ_name_or_oid, "0123456789") == strlen(typ_name_or_oid))
  	{
! 		result = DatumGetObjectId(DirectFunctionCall1(oidin,
  										  CStringGetDatum(typ_name_or_oid)));
! 		PG_RETURN_OID(result);
  	}
  
  	/* Else it's a type name, possibly schema-qualified or decorated */
--- 1108,1167 ----
  regtypein(PG_FUNCTION_ARGS)
  {
  	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result;
! 
! 	if (!regtype_guts(typ_name_or_oid, &result, false))
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_OBJECT),
! 				 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
! 
! 	PG_RETURN_OID(result);
! }
! 
! /*
!  * to_regtype		- converts "typename" to type OID
!  *
!  * Diffrence from regtypein is, this does not throw an error if the typename
!  * does not exist.
!  * Note: this is not an I/O function.
!  */
! Datum
! to_regtype(PG_FUNCTION_ARGS)
! {
! 	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result;
! 
! 	if (regtype_guts(typ_name_or_oid, &result, true))
! 		PG_RETURN_OID(result);
! 	else
! 		PG_RETURN_NULL();
! }
! 
! /*
!  * Guts of regtypein and to_regtype.
!  * If the classname is found, returns true and the OID is stored into *typid_p.
!  * If not found and missing_ok is true, or in bootstrap mode, returns false instead
!  * of raising an error
!  */
! static bool
! regtype_guts(char *typ_name_or_oid, Oid *typid_p, bool missing_ok)
! {
  	int32		typmod;
  
+ 	*typid_p = InvalidOid;
+ 
  	/* '-' ? */
  	if (strcmp(typ_name_or_oid, "-") == 0)
! 		return true;
  
  	/* Numeric OID? */
  	if (typ_name_or_oid[0] >= '0' &&
  		typ_name_or_oid[0] <= '9' &&
  		strspn(typ_name_or_oid, "0123456789") == strlen(typ_name_or_oid))
  	{
! 		*typid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
  										  CStringGetDatum(typ_name_or_oid)));
! 		return true;
  	}
  
  	/* Else it's a type name, possibly schema-qualified or decorated */
*************** regtypein(PG_FUNCTION_ARGS)
*** 1010,1036 ****
  									 NULL, 1, skey);
  
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
! 			result = HeapTupleGetOid(tuple);
  		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_OBJECT),
! 					 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
  
  		/* We assume there can be only one match */
  
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		PG_RETURN_OID(result);
  	}
  
  	/*
  	 * Normal case: invoke the full parser to deal with special cases such as
  	 * array syntax.
  	 */
! 	parseTypeString(typ_name_or_oid, &result, &typmod);
  
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 1189,1213 ----
  									 NULL, 1, skey);
  
  		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
! 			*typid_p = HeapTupleGetOid(tuple);
  		else
! 			return false;
  
  		/* We assume there can be only one match */
  
  		systable_endscan(sysscan);
  		heap_close(hdesc, AccessShareLock);
  
! 		return true;
  	}
  
  	/*
  	 * Normal case: invoke the full parser to deal with special cases such as
  	 * array syntax.
  	 */
! 	parseTypeString(typ_name_or_oid, typid_p, &typmod, missing_ok);
  
! 	return OidIsValid(*typid_p);
  }
  
  /*
*************** parseNameAndArgTypes(const char *string,
*** 1523,1529 ****
  		else
  		{
  			/* Use full parser to resolve the type name */
! 			parseTypeString(typename, &typeid, &typmod);
  		}
  		if (*nargs >= FUNC_MAX_ARGS)
  			ereport(ERROR,
--- 1700,1706 ----
  		else
  		{
  			/* Use full parser to resolve the type name */
! 			parseTypeString(typename, &typeid, &typmod, false);
  		}
  		if (*nargs >= FUNC_MAX_ARGS)
  			ereport(ERROR,
diff --git a/src/include/catalog/namespace.h b/src/include/catalog/namespace.h
new file mode 100644
index b30e5e8..2f9d391
*** a/src/include/catalog/namespace.h
--- b/src/include/catalog/namespace.h
*************** extern FuncCandidateList FuncnameGetCand
*** 76,82 ****
  extern bool FunctionIsVisible(Oid funcid);
  
  extern Oid	OpernameGetOprid(List *names, Oid oprleft, Oid oprright);
! extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind);
  extern bool OperatorIsVisible(Oid oprid);
  
  extern Oid	OpclassnameGetOpcid(Oid amid, const char *opcname);
--- 76,83 ----
  extern bool FunctionIsVisible(Oid funcid);
  
  extern Oid	OpernameGetOprid(List *names, Oid oprleft, Oid oprright);
! extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind,
! 					  bool missing_schema_ok);
  extern bool OperatorIsVisible(Oid oprid);
  
  extern Oid	OpclassnameGetOpcid(Oid amid, const char *opcname);
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
new file mode 100644
index e33670c..9897d18
*** a/src/include/catalog/pg_proc.h
--- b/src/include/catalog/pg_proc.h
*************** DATA(insert OID =  44 (  regprocin		   P
*** 173,178 ****
--- 173,180 ----
  DESCR("I/O");
  DATA(insert OID =  45 (  regprocout		   PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "24" _null_ _null_ _null_ _null_ regprocout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3208 (  to_regproc		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 24 "2275" _null_ _null_ _null_ _null_ to_regproc _null_ _null_ _null_ ));
+ DESCR("convert proname to regproc");
  DATA(insert OID =  46 (  textin			   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 25 "2275" _null_ _null_ _null_ _null_ textin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID =  47 (  textout		   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2275 "25" _null_ _null_ _null_ _null_ textout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2214 (  regoperin			PG
*** 3304,3309 ****
--- 3306,3313 ----
  DESCR("I/O");
  DATA(insert OID = 2215 (  regoperout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2203" _null_ _null_ _null_ _null_ regoperout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3206 (  to_regoper		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2203 "2275" _null_ _null_ _null_ _null_ to_regoper _null_ _null_ _null_ ));
+ DESCR("convert operator name to regoper");
  DATA(insert OID = 2216 (  regoperatorin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2204 "2275" _null_ _null_ _null_ _null_ regoperatorin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2217 (  regoperatorout	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2204" _null_ _null_ _null_ _null_ regoperatorout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2218 (  regclassin		PG
*** 3312,3321 ****
--- 3316,3329 ----
  DESCR("I/O");
  DATA(insert OID = 2219 (  regclassout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2205" _null_ _null_ _null_ _null_ regclassout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3209 (  to_regclass		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "2275" _null_ _null_ _null_ _null_ to_regclass _null_ _null_ _null_ ));
+ DESCR("convert classname to regclass");
  DATA(insert OID = 2220 (  regtypein			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ regtypein _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2221 (  regtypeout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2206" _null_ _null_ _null_ _null_ regtypeout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3207 (  to_regtype		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ to_regtype _null_ _null_ _null_ ));
+ DESCR("convert type name to regtype");
  DATA(insert OID = 1079 (  regclass			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "25" _null_ _null_ _null_ _null_	text_regclass _null_ _null_ _null_ ));
  DESCR("convert text to regclass");
  
diff --git a/src/include/parser/parse_type.h b/src/include/parser/parse_type.h
new file mode 100644
index ab73148..fa9cc59
*** a/src/include/parser/parse_type.h
--- b/src/include/parser/parse_type.h
*************** extern Datum stringTypeDatum(Type tp, ch
*** 47,53 ****
  
  extern Oid	typeidTypeRelid(Oid type_id);
  
! extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p);
  
  #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
  
--- 47,53 ----
  
  extern Oid	typeidTypeRelid(Oid type_id);
  
! extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p, bool missing_ok);
  
  #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
  
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
new file mode 100644
index b90d88d..85dee8a
*** a/src/include/utils/builtins.h
--- b/src/include/utils/builtins.h
*************** extern char *regexp_fixed_prefix(text *t
*** 597,602 ****
--- 597,603 ----
  /* regproc.c */
  extern Datum regprocin(PG_FUNCTION_ARGS);
  extern Datum regprocout(PG_FUNCTION_ARGS);
+ extern Datum to_regproc(PG_FUNCTION_ARGS);
  extern Datum regprocrecv(PG_FUNCTION_ARGS);
  extern Datum regprocsend(PG_FUNCTION_ARGS);
  extern Datum regprocedurein(PG_FUNCTION_ARGS);
*************** extern Datum regoperin(PG_FUNCTION_ARGS)
*** 607,612 ****
--- 608,614 ----
  extern Datum regoperout(PG_FUNCTION_ARGS);
  extern Datum regoperrecv(PG_FUNCTION_ARGS);
  extern Datum regopersend(PG_FUNCTION_ARGS);
+ extern Datum to_regoper(PG_FUNCTION_ARGS);
  extern Datum regoperatorin(PG_FUNCTION_ARGS);
  extern Datum regoperatorout(PG_FUNCTION_ARGS);
  extern Datum regoperatorrecv(PG_FUNCTION_ARGS);
*************** extern Datum regclassin(PG_FUNCTION_ARGS
*** 615,624 ****
--- 617,628 ----
  extern Datum regclassout(PG_FUNCTION_ARGS);
  extern Datum regclassrecv(PG_FUNCTION_ARGS);
  extern Datum regclasssend(PG_FUNCTION_ARGS);
+ extern Datum to_regclass(PG_FUNCTION_ARGS);
  extern Datum regtypein(PG_FUNCTION_ARGS);
  extern Datum regtypeout(PG_FUNCTION_ARGS);
  extern Datum regtyperecv(PG_FUNCTION_ARGS);
  extern Datum regtypesend(PG_FUNCTION_ARGS);
+ extern Datum to_regtype(PG_FUNCTION_ARGS);
  extern Datum regconfigin(PG_FUNCTION_ARGS);
  extern Datum regconfigout(PG_FUNCTION_ARGS);
  extern Datum regconfigrecv(PG_FUNCTION_ARGS);
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
new file mode 100644
index f8ccaa5..adf1f68
*** a/src/pl/plperl/plperl.c
--- b/src/pl/plperl/plperl.c
*************** plperl_spi_prepare(char *query, int argc
*** 3405,3411 ****
  			char	   *typstr;
  
  			typstr = sv2cstr(argv[i]);
! 			parseTypeString(typstr, &typId, &typmod);
  			pfree(typstr);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
--- 3405,3411 ----
  			char	   *typstr;
  
  			typstr = sv2cstr(argv[i]);
! 			parseTypeString(typstr, &typId, &typmod, false);
  			pfree(typstr);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
new file mode 100644
index c0cb585..1862293
*** a/src/pl/plpgsql/src/pl_gram.y
--- b/src/pl/plpgsql/src/pl_gram.y
*************** parse_datatype(const char *string, int l
*** 3462,3468 ****
  	error_context_stack = &syntax_errcontext;
  
  	/* Let the main parser try to parse it under standard SQL rules */
! 	parseTypeString(string, &type_id, &typmod);
  
  	/* Restore former ereport callback */
  	error_context_stack = syntax_errcontext.previous;
--- 3462,3468 ----
  	error_context_stack = &syntax_errcontext;
  
  	/* Let the main parser try to parse it under standard SQL rules */
! 	parseTypeString(string, &type_id, &typmod, false);
  
  	/* Restore former ereport callback */
  	error_context_stack = syntax_errcontext.previous;
diff --git a/src/pl/plpython/plpy_spi.c b/src/pl/plpython/plpy_spi.c
new file mode 100644
index 982bf84..060d514
*** a/src/pl/plpython/plpy_spi.c
--- b/src/pl/plpython/plpy_spi.c
*************** PLy_spi_prepare(PyObject *self, PyObject
*** 113,119 ****
  			 *information for input conversion.
  			 ********************************************************/
  
! 			parseTypeString(sptr, &typeId, &typmod);
  
  			typeTup = SearchSysCache1(TYPEOID,
  									  ObjectIdGetDatum(typeId));
--- 113,119 ----
  			 *information for input conversion.
  			 ********************************************************/
  
! 			parseTypeString(sptr, &typeId, &typmod, false);
  
  			typeTup = SearchSysCache1(TYPEOID,
  									  ObjectIdGetDatum(typeId));
diff --git a/src/pl/tcl/pltcl.c b/src/pl/tcl/pltcl.c
new file mode 100644
index b3bf65e..2d862a6
*** a/src/pl/tcl/pltcl.c
--- b/src/pl/tcl/pltcl.c
*************** pltcl_SPI_prepare(ClientData cdata, Tcl_
*** 2165,2171 ****
  						typIOParam;
  			int32		typmod;
  
! 			parseTypeString(args[i], &typId, &typmod);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
  
--- 2165,2171 ----
  						typIOParam;
  			int32		typmod;
  
! 			parseTypeString(args[i], &typId, &typmod, false);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
  
diff --git a/src/test/regress/expected/regproc.out b/src/test/regress/expected/regproc.out
new file mode 100644
index ...9f8d8e8
*** a/src/test/regress/expected/regproc.out
--- b/src/test/regress/expected/regproc.out
***************
*** 0 ****
--- 1,237 ----
+ --
+ -- regproc
+ --
+ /* If objects exist, return oids */
+ -- without schemaname
+ SELECT regoper('||/');
+  regoper 
+ ---------
+  ||/
+ (1 row)
+ 
+ SELECT regproc('now');
+  regproc 
+ ---------
+  now
+ (1 row)
+ 
+ SELECT regclass('pg_class');
+  regclass 
+ ----------
+  pg_class
+ (1 row)
+ 
+ SELECT regtype('int4');
+  regtype 
+ ---------
+  integer
+ (1 row)
+ 
+ SELECT to_regoper('||/');
+  to_regoper 
+ ------------
+  ||/
+ (1 row)
+ 
+ SELECT to_regproc('now');
+  to_regproc 
+ ------------
+  now
+ (1 row)
+ 
+ SELECT to_regclass('pg_class');
+  to_regclass 
+ -------------
+  pg_class
+ (1 row)
+ 
+ SELECT to_regtype('int4');
+  to_regtype 
+ ------------
+  integer
+ (1 row)
+ 
+ -- with schemaname
+ SELECT regoper('pg_catalog.||/');
+  regoper 
+ ---------
+  ||/
+ (1 row)
+ 
+ SELECT regproc('pg_catalog.now');
+  regproc 
+ ---------
+  now
+ (1 row)
+ 
+ SELECT regclass('pg_catalog.pg_class');
+  regclass 
+ ----------
+  pg_class
+ (1 row)
+ 
+ SELECT regtype('pg_catalog.int4');
+  regtype 
+ ---------
+  integer
+ (1 row)
+ 
+ SELECT to_regoper('pg_catalog.||/');
+  to_regoper 
+ ------------
+  ||/
+ (1 row)
+ 
+ SELECT to_regproc('pg_catalog.now');
+  to_regproc 
+ ------------
+  now
+ (1 row)
+ 
+ SELECT to_regclass('pg_catalog.pg_class');
+  to_regclass 
+ -------------
+  pg_class
+ (1 row)
+ 
+ SELECT to_regtype('pg_catalog.int4');
+  to_regtype 
+ ------------
+  integer
+ (1 row)
+ 
+ /* If objects don't exist, raise errors. */
+ -- without schemaname
+ SELECT regoper('||//');
+ ERROR:  operator does not exist: ||//
+ LINE 3: SELECT regoper('||//');
+                        ^
+ SELECT regproc('know');
+ ERROR:  function "know" does not exist
+ LINE 1: SELECT regproc('know');
+                        ^
+ SELECT regclass('pg_classes');
+ ERROR:  relation "pg_classes" does not exist
+ LINE 1: SELECT regclass('pg_classes');
+                         ^
+ SELECT regtype('int3');
+ ERROR:  type "int3" does not exist
+ LINE 1: SELECT regtype('int3');
+                        ^
+ -- with schemaname
+ SELECT regoper('ng_catalog.||/');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regoper('ng_catalog.||/');
+                        ^
+ SELECT regproc('ng_catalog.now');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regproc('ng_catalog.now');
+                        ^
+ SELECT regclass('ng_catalog.pg_class');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regclass('ng_catalog.pg_class');
+                         ^
+ SELECT regtype('ng_catalog.int4');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regtype('ng_catalog.int4');
+                        ^
+ /* If objects don't exist, return NULL with no error. */
+ -- without schemaname
+ SELECT to_regoper('||//');
+  to_regoper 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regproc('know');
+  to_regproc 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regclass('pg_classes');
+  to_regclass 
+ -------------
+  
+ (1 row)
+ 
+ SELECT to_regtype('int3');
+  to_regtype 
+ ------------
+  
+ (1 row)
+ 
+ -- with schemaname
+ SELECT to_regoper('ng_catalog.||/');
+  to_regoper 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regproc('ng_catalog.now');
+  to_regproc 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regclass('ng_catalog.pg_class');
+  to_regclass 
+ -------------
+  
+ (1 row)
+ 
+ SELECT to_regtype('ng_catalog.int4');
+  to_regtype 
+ ------------
+  
+ (1 row)
+ 
+ /* Cast 0 to InvalidOid */
+ SELECT regoper('0');
+  regoper 
+ ---------
+  0
+ (1 row)
+ 
+ SELECT regproc('0');
+  regproc 
+ ---------
+  -
+ (1 row)
+ 
+ SELECT regclass('0');
+  regclass 
+ ----------
+  -
+ (1 row)
+ 
+ SELECT regtype('0');
+  regtype 
+ ---------
+  -
+ (1 row)
+ 
+ SELECT to_regoper('0');
+  to_regoper 
+ ------------
+  0
+ (1 row)
+ 
+ SELECT to_regproc('0');
+  to_regproc 
+ ------------
+  -
+ (1 row)
+ 
+ SELECT to_regclass('0');
+  to_regclass 
+ -------------
+  -
+ (1 row)
+ 
+ SELECT to_regtype('0');
+  to_regtype 
+ ------------
+  -
+ (1 row)
+ 
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
new file mode 100644
index 2e3eba8..d83421e
*** a/src/test/regress/parallel_schedule
--- b/src/test/regress/parallel_schedule
*************** test: tablespace
*** 13,19 ****
  # ----------
  # The first group of parallel tests
  # ----------
! test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes pg_lsn
  
  # Depends on things setup during char, varchar and text
  test: strings
--- 13,19 ----
  # ----------
  # The first group of parallel tests
  # ----------
! test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes pg_lsn regproc
  
  # Depends on things setup during char, varchar and text
  test: strings
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
new file mode 100644
index 4f1dede..e5d6975
*** a/src/test/regress/serial_schedule
--- b/src/test/regress/serial_schedule
*************** test: enum
*** 20,25 ****
--- 20,26 ----
  test: money
  test: rangetypes
  test: pg_lsn
+ test: regproc
  test: strings
  test: numerology
  test: point
diff --git a/src/test/regress/sql/regproc.sql b/src/test/regress/sql/regproc.sql
new file mode 100644
index ...3cfa726
*** a/src/test/regress/sql/regproc.sql
--- b/src/test/regress/sql/regproc.sql
***************
*** 0 ****
--- 1,74 ----
+ --
+ -- regproc
+ --
+ 
+ /* If objects exist, return oids */
+ 
+ -- without schemaname
+ 
+ SELECT regoper('||/');
+ SELECT regproc('now');
+ SELECT regclass('pg_class');
+ SELECT regtype('int4');
+ 
+ SELECT to_regoper('||/');
+ SELECT to_regproc('now');
+ SELECT to_regclass('pg_class');
+ SELECT to_regtype('int4');
+ 
+ -- with schemaname
+ 
+ SELECT regoper('pg_catalog.||/');
+ SELECT regproc('pg_catalog.now');
+ SELECT regclass('pg_catalog.pg_class');
+ SELECT regtype('pg_catalog.int4');
+ 
+ SELECT to_regoper('pg_catalog.||/');
+ SELECT to_regproc('pg_catalog.now');
+ SELECT to_regclass('pg_catalog.pg_class');
+ SELECT to_regtype('pg_catalog.int4');
+ 
+ /* If objects don't exist, raise errors. */
+ 
+ -- without schemaname
+ 
+ SELECT regoper('||//');
+ SELECT regproc('know');
+ SELECT regclass('pg_classes');
+ SELECT regtype('int3');
+ 
+ -- with schemaname
+ 
+ SELECT regoper('ng_catalog.||/');
+ SELECT regproc('ng_catalog.now');
+ SELECT regclass('ng_catalog.pg_class');
+ SELECT regtype('ng_catalog.int4');
+ 
+ /* If objects don't exist, return NULL with no error. */
+ 
+ -- without schemaname
+ 
+ SELECT to_regoper('||//');
+ SELECT to_regproc('know');
+ SELECT to_regclass('pg_classes');
+ SELECT to_regtype('int3');
+ 
+ -- with schemaname
+ 
+ SELECT to_regoper('ng_catalog.||/');
+ SELECT to_regproc('ng_catalog.now');
+ SELECT to_regclass('ng_catalog.pg_class');
+ SELECT to_regtype('ng_catalog.int4');
+ 
+ /* Cast 0 to InvalidOid */
+ 
+ SELECT regoper('0');
+ SELECT regproc('0');
+ SELECT regclass('0');
+ SELECT regtype('0');
+ 
+ SELECT to_regoper('0');
+ SELECT to_regproc('0');
+ SELECT to_regclass('0');
+ SELECT to_regtype('0');
+ 

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
new file mode 100644
index 6e2fbda..10e7578
*** a/doc/src/sgml/func.sgml
--- b/doc/src/sgml/func.sgml
*************** SELECT pg_type_is_visible('myschema.widg
*** 15279,15284 ****
--- 15279,15300 ----
      <primary>collation for</primary>
     </indexterm>
  
+    <indexterm>
+     <primary>to_regclass</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regproc</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regoper</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regtype</primary>
+    </indexterm>
+ 
    <para>
     <xref linkend="functions-info-catalog-table"> lists functions that
     extract information from the system catalogs.
*************** SELECT pg_type_is_visible('myschema.widg
*** 15449,15454 ****
--- 15465,15490 ----
         <entry><type>text</type></entry>
         <entry>get the collation of the argument</entry>
        </row>
+       <row>
+        <entry><literal><function>to_regclass(<parameter>rel_name</parameter>)</function></literal></entry>
+        <entry><type>regclass</type></entry>
+        <entry>get the relation oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regproc(<parameter>func_name</parameter>)</function></literal></entry>
+        <entry><type>regproc</type></entry>
+        <entry>get the function oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regoper(<parameter>operator_name</parameter>)</function></literal></entry>
+        <entry><type>regoper</type></entry>
+        <entry>get the operator oid</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regtype(<parameter>type_name</parameter>)</function></literal></entry>
+        <entry><type>regtype</type></entry>
+        <entry>get the type oid</entry>
+       </row>
       </tbody>
      </tgroup>
     </table>
*************** SELECT collation for ('foo' COLLATE "de_
*** 15614,15619 ****
--- 15650,15668 ----
    is not of a collatable data type, then an error is raised.
    </para>
  
+   <para>
+    <function>to_regclass</function>, <function>to_regproc</function>,
+    <function>to_regoper</function> and <function>to_regtype</function> are
+    functions similar to type casting to the object identifier types:
+    <type>regclass</>, <type>regproc</>, <type>regoper</> and <type>regtype</>,
+    except that they return NULL when the object is not found, instead of
+    raising an error. In addition, neither <function>to_regproc</function> nor
+    <function>to_regoper</function> doesn't raise an error when more than one
+    object are found. Note that these are just fuctions but not type casting, so
+    these behave differently for creation of dependencies when used as default
+    values of columns.
+   </para>
+ 
     <indexterm>
      <primary>col_description</primary>
     </indexterm>
diff --git a/src/backend/catalog/namespace.c b/src/backend/catalog/namespace.c
new file mode 100644
index 6c2a5d2..5bf6d28
*** a/src/backend/catalog/namespace.c
--- b/src/backend/catalog/namespace.c
*************** OpernameGetOprid(List *names, Oid oprlef
*** 1556,1562 ****
   * will be InvalidOid for a prefix or postfix oprkind.	nargs is 2, too.
   */
  FuncCandidateList
! OpernameGetCandidates(List *names, char oprkind)
  {
  	FuncCandidateList resultList = NULL;
  	char	   *resultSpace = NULL;
--- 1556,1562 ----
   * will be InvalidOid for a prefix or postfix oprkind.	nargs is 2, too.
   */
  FuncCandidateList
! OpernameGetCandidates(List *names, char oprkind, bool missing_schema_ok)
  {
  	FuncCandidateList resultList = NULL;
  	char	   *resultSpace = NULL;
*************** OpernameGetCandidates(List *names, char 
*** 1573,1579 ****
  	if (schemaname)
  	{
  		/* use exact schema given */
! 		namespaceId = LookupExplicitNamespace(schemaname, false);
  	}
  	else
  	{
--- 1573,1581 ----
  	if (schemaname)
  	{
  		/* use exact schema given */
! 		namespaceId = LookupExplicitNamespace(schemaname, missing_schema_ok);
! 		if (missing_schema_ok && !OidIsValid(namespaceId))
! 			return NULL;
  	}
  	else
  	{
diff --git a/src/backend/parser/parse_oper.c b/src/backend/parser/parse_oper.c
new file mode 100644
index 99dbd30..a2b712d
*** a/src/backend/parser/parse_oper.c
--- b/src/backend/parser/parse_oper.c
*************** oper(ParseState *pstate, List *opname, O
*** 407,413 ****
  		FuncCandidateList clist;
  
  		/* Get binary operators of given name */
! 		clist = OpernameGetCandidates(opname, 'b');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 407,413 ----
  		FuncCandidateList clist;
  
  		/* Get binary operators of given name */
! 		clist = OpernameGetCandidates(opname, 'b', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
*************** right_oper(ParseState *pstate, List *op,
*** 553,559 ****
  		FuncCandidateList clist;
  
  		/* Get postfix operators of given name */
! 		clist = OpernameGetCandidates(op, 'r');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 553,559 ----
  		FuncCandidateList clist;
  
  		/* Get postfix operators of given name */
! 		clist = OpernameGetCandidates(op, 'r', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
*************** left_oper(ParseState *pstate, List *op, 
*** 631,637 ****
  		FuncCandidateList clist;
  
  		/* Get prefix operators of given name */
! 		clist = OpernameGetCandidates(op, 'l');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 631,637 ----
  		FuncCandidateList clist;
  
  		/* Get prefix operators of given name */
! 		clist = OpernameGetCandidates(op, 'l', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
new file mode 100644
index b329dfb..d8f191e
*** a/src/backend/parser/parse_type.c
--- b/src/backend/parser/parse_type.c
*************** pts_error_callback(void *arg)
*** 706,714 ****
   * Given a string that is supposed to be a SQL-compatible type declaration,
   * such as "int4" or "integer" or "character varying(32)", parse
   * the string and convert it to a type OID and type modifier.
   */
  void
! parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p)
  {
  	StringInfoData buf;
  	List	   *raw_parsetree_list;
--- 706,717 ----
   * Given a string that is supposed to be a SQL-compatible type declaration,
   * such as "int4" or "integer" or "character varying(32)", parse
   * the string and convert it to a type OID and type modifier.
+  * If the type name is not found, return InvalidOid if missing_ok
+  * = true, otherwise raise an error.
   */
  void
! parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p,
! 				bool missing_ok)
  {
  	StringInfoData buf;
  	List	   *raw_parsetree_list;
*************** parseTypeString(const char *str, Oid *ty
*** 717,722 ****
--- 720,726 ----
  	TypeCast   *typecast;
  	TypeName   *typeName;
  	ErrorContextCallback ptserrcontext;
+ 	Type		tup;
  
  	/* make sure we give useful error for empty input */
  	if (strspn(str, " \t\n\r\f") == strlen(str))
*************** parseTypeString(const char *str, Oid *ty
*** 782,789 ****
  	if (typeName->setof)
  		goto fail;
  
! 	typenameTypeIdAndMod(NULL, typeName, typeid_p, typmod_p);
  
  	pfree(buf.data);
  
  	return;
--- 786,817 ----
  	if (typeName->setof)
  		goto fail;
  
! 	tup = LookupTypeName(NULL, typeName, typmod_p, missing_ok);
! 	if (tup == NULL)
! 	{
! 		if (!missing_ok)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_OBJECT),
! 					errmsg("type \"%s\" does not exist",
! 							TypeNameToString(typeName)),
! 					parser_errposition(NULL, typeName->location)));
! 		else
! 		{
! 			*typeid_p = InvalidOid;
! 			pfree(buf.data);
! 			return;
! 		}
! 	}
! 
! 	if (!((Form_pg_type) GETSTRUCT(tup))->typisdefined)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_OBJECT),
! 				errmsg("type \"%s\" is only a shell",
! 						TypeNameToString(typeName)),
! 				parser_errposition(NULL, typeName->location)));
! 	*typeid_p = HeapTupleGetOid(tup);
  
+ 	ReleaseSysCache(tup);
  	pfree(buf.data);
  
  	return;
diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
new file mode 100644
index 5d73562..08f116e
*** a/src/backend/utils/adt/regproc.c
--- b/src/backend/utils/adt/regproc.c
*************** static char *format_operator_internal(Oi
*** 45,50 ****
--- 45,54 ----
  static char *format_procedure_internal(Oid procedure_oid, bool force_qualify);
  static void parseNameAndArgTypes(const char *string, bool allowNone,
  					 List **names, int *nargs, Oid *argtypes);
+ static bool regproc_guts(char *pro_name_or_oid, Oid *proid_p, bool missing_ok);
+ static bool regoper_guts(char *opr_name_or_oid, RegProcedure *oprid_p, bool missing_ok);
+ static bool regclass_guts(char *class_name_or_oid, Oid *classid_p, bool missing_ok);
+ static bool regtype_guts(char *typ_name_or_oid, Oid *typid_p, bool missing_ok);
  
  
  /*****************************************************************************
*************** Datum
*** 63,155 ****
  regprocin(PG_FUNCTION_ARGS)
  {
  	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
! 	RegProcedure result = InvalidOid;
! 	List	   *names;
! 	FuncCandidateList clist;
! 
! 	/* '-' ? */
! 	if (strcmp(pro_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
! 
! 	/* Numeric OID? */
! 	if (pro_name_or_oid[0] >= '0' &&
! 		pro_name_or_oid[0] <= '9' &&
! 		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
! 	{
! 		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(pro_name_or_oid)));
! 		PG_RETURN_OID(result);
! 	}
! 
! 	/* Else it's a name, possibly schema-qualified */
! 
! 	/*
! 	 * In bootstrap mode we assume the given name is not schema-qualified, and
! 	 * just search pg_proc for a unique match.	This is needed for
! 	 * initializing other system catalogs (pg_namespace may not exist yet, and
! 	 * certainly there are no schemas other than pg_catalog).
! 	 */
! 	if (IsBootstrapProcessingMode())
! 	{
! 		int			matches = 0;
! 		Relation	hdesc;
! 		ScanKeyData skey[1];
! 		SysScanDesc sysscan;
! 		HeapTuple	tuple;
! 
! 		ScanKeyInit(&skey[0],
! 					Anum_pg_proc_proname,
! 					BTEqualStrategyNumber, F_NAMEEQ,
! 					CStringGetDatum(pro_name_or_oid));
! 
! 		hdesc = heap_open(ProcedureRelationId, AccessShareLock);
! 		sysscan = systable_beginscan(hdesc, ProcedureNameArgsNspIndexId, true,
! 									 NULL, 1, skey);
! 
! 		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
! 		{
! 			result = (RegProcedure) HeapTupleGetOid(tuple);
! 			if (++matches > 1)
! 				break;
! 		}
! 
! 		systable_endscan(sysscan);
! 		heap_close(hdesc, AccessShareLock);
  
! 		if (matches == 0)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
  
! 		else if (matches > 1)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one function named \"%s\"",
! 							pro_name_or_oid)));
  
  		PG_RETURN_OID(result);
! 	}
! 
! 	/*
! 	 * Normal case: parse the name into components and see if it matches any
! 	 * pg_proc entries in the current search path.
! 	 */
! 	names = stringToQualifiedNameList(pro_name_or_oid);
! 	clist = FuncnameGetCandidates(names, -1, NIL, false, false, false);
! 
! 	if (clist == NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
! 	else if (clist->next != NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 				 errmsg("more than one function named \"%s\"",
! 						pro_name_or_oid)));
! 
! 	result = clist->oid;
! 
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 67,95 ----
  regprocin(PG_FUNCTION_ARGS)
  {
  	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
! 	RegProcedure result;
  
! 	regproc_guts(pro_name_or_oid, &result, false);
! 	PG_RETURN_OID(result);
! }
  
! /*
!  * to_regproc	- converts "proname" to proc OID
!  *
!  * This function differs from regprocin only in returning NULL and not raising
!  * an error when the proname is not found or more than one proname is found.
!  * Note that this is not an I/O function.
!  */
! Datum
! to_regproc(PG_FUNCTION_ARGS)
! {
! 	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
! 	RegProcedure result;
  
+ 	if (regproc_guts(pro_name_or_oid, &result, true))
  		PG_RETURN_OID(result);
! 	else
! 		PG_RETURN_NULL();
  }
  
  /*
*************** Datum
*** 431,522 ****
  regoperin(PG_FUNCTION_ARGS)
  {
  	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result = InvalidOid;
! 	List	   *names;
! 	FuncCandidateList clist;
! 
! 	/* '0' ? */
! 	if (strcmp(opr_name_or_oid, "0") == 0)
! 		PG_RETURN_OID(InvalidOid);
! 
! 	/* Numeric OID? */
! 	if (opr_name_or_oid[0] >= '0' &&
! 		opr_name_or_oid[0] <= '9' &&
! 		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
! 	{
! 		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(opr_name_or_oid)));
! 		PG_RETURN_OID(result);
! 	}
! 
! 	/* Else it's a name, possibly schema-qualified */
! 
! 	/*
! 	 * In bootstrap mode we assume the given name is not schema-qualified, and
! 	 * just search pg_operator for a unique match.	This is needed for
! 	 * initializing other system catalogs (pg_namespace may not exist yet, and
! 	 * certainly there are no schemas other than pg_catalog).
! 	 */
! 	if (IsBootstrapProcessingMode())
! 	{
! 		int			matches = 0;
! 		Relation	hdesc;
! 		ScanKeyData skey[1];
! 		SysScanDesc sysscan;
! 		HeapTuple	tuple;
! 
! 		ScanKeyInit(&skey[0],
! 					Anum_pg_operator_oprname,
! 					BTEqualStrategyNumber, F_NAMEEQ,
! 					CStringGetDatum(opr_name_or_oid));
! 
! 		hdesc = heap_open(OperatorRelationId, AccessShareLock);
! 		sysscan = systable_beginscan(hdesc, OperatorNameNspIndexId, true,
! 									 NULL, 1, skey);
! 
! 		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
! 		{
! 			result = HeapTupleGetOid(tuple);
! 			if (++matches > 1)
! 				break;
! 		}
  
! 		systable_endscan(sysscan);
! 		heap_close(hdesc, AccessShareLock);
  
! 		if (matches == 0)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 					 errmsg("operator does not exist: %s", opr_name_or_oid)));
! 		else if (matches > 1)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 					 errmsg("more than one operator named %s",
! 							opr_name_or_oid)));
  
  		PG_RETURN_OID(result);
! 	}
! 
! 	/*
! 	 * Normal case: parse the name into components and see if it matches any
! 	 * pg_operator entries in the current search path.
! 	 */
! 	names = stringToQualifiedNameList(opr_name_or_oid);
! 	clist = OpernameGetCandidates(names, '\0');
! 
! 	if (clist == NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_FUNCTION),
! 				 errmsg("operator does not exist: %s", opr_name_or_oid)));
! 	else if (clist->next != NULL)
! 		ereport(ERROR,
! 				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
! 				 errmsg("more than one operator named %s",
! 						opr_name_or_oid)));
! 
! 	result = clist->oid;
! 
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 371,399 ----
  regoperin(PG_FUNCTION_ARGS)
  {
  	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result;
  
! 	regoper_guts(opr_name_or_oid, &result, false);
! 	PG_RETURN_OID(result);
! }
  
! /*
!  * to_regoper		- converts "oprname" to operator OID
!  *
!  * This function differs from regoperin only in returning NULL and not raising
!  * an error when the opername is not found or more than one opername is found.
!  * Note that this is not an I/O function.
!  */
! Datum
! to_regoper(PG_FUNCTION_ARGS)
! {
! 	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result;
  
+ 	if (regoper_guts(opr_name_or_oid, &result, true))
  		PG_RETURN_OID(result);
! 	else
! 		PG_RETURN_NULL();
  }
  
  /*
*************** regoperout(PG_FUNCTION_ARGS)
*** 558,564 ****
  			 * qualify it.
  			 */
  			clist = OpernameGetCandidates(list_make1(makeString(oprname)),
! 										  '\0');
  			if (clist != NULL && clist->next == NULL &&
  				clist->oid == oprid)
  				result = pstrdup(oprname);
--- 435,441 ----
  			 * qualify it.
  			 */
  			clist = OpernameGetCandidates(list_make1(makeString(oprname)),
! 										  '\0', false);
  			if (clist != NULL && clist->next == NULL &&
  				clist->oid == oprid)
  				result = pstrdup(oprname);
*************** Datum
*** 804,875 ****
  regclassin(PG_FUNCTION_ARGS)
  {
  	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result = InvalidOid;
! 	List	   *names;
! 
! 	/* '-' ? */
! 	if (strcmp(class_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
! 
! 	/* Numeric OID? */
! 	if (class_name_or_oid[0] >= '0' &&
! 		class_name_or_oid[0] <= '9' &&
! 		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
! 	{
! 		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										CStringGetDatum(class_name_or_oid)));
! 		PG_RETURN_OID(result);
! 	}
! 
! 	/* Else it's a name, possibly schema-qualified */
! 
! 	/*
! 	 * In bootstrap mode we assume the given name is not schema-qualified, and
! 	 * just search pg_class for a match.  This is needed for initializing
! 	 * other system catalogs (pg_namespace may not exist yet, and certainly
! 	 * there are no schemas other than pg_catalog).
! 	 */
! 	if (IsBootstrapProcessingMode())
! 	{
! 		Relation	hdesc;
! 		ScanKeyData skey[1];
! 		SysScanDesc sysscan;
! 		HeapTuple	tuple;
! 
! 		ScanKeyInit(&skey[0],
! 					Anum_pg_class_relname,
! 					BTEqualStrategyNumber, F_NAMEEQ,
! 					CStringGetDatum(class_name_or_oid));
! 
! 		hdesc = heap_open(RelationRelationId, AccessShareLock);
! 		sysscan = systable_beginscan(hdesc, ClassNameNspIndexId, true,
! 									 NULL, 1, skey);
  
! 		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
! 			result = HeapTupleGetOid(tuple);
! 		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_TABLE),
! 			   errmsg("relation \"%s\" does not exist", class_name_or_oid)));
  
! 		/* We assume there can be only one match */
  
! 		systable_endscan(sysscan);
! 		heap_close(hdesc, AccessShareLock);
  
  		PG_RETURN_OID(result);
! 	}
! 
! 	/*
! 	 * Normal case: parse the name into components and see if it matches any
! 	 * pg_class entries in the current search path.
! 	 */
! 	names = stringToQualifiedNameList(class_name_or_oid);
! 
! 	/* We might not even have permissions on this relation; don't lock it. */
! 	result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, false);
! 
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 681,713 ----
  regclassin(PG_FUNCTION_ARGS)
  {
  	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result;
  
! 	if (!regclass_guts(class_name_or_oid, &result, false))
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_TABLE),
! 				 errmsg("relation \"%s\" does not exist", class_name_or_oid)));
  
! 	PG_RETURN_OID(result);
! }
  
! /*
!  * to_regclass		- converts "classname" to class OID
!  *
!  * This function differs from regclassin only in returning NULL and not raising
!  * an error when the classname is not found. Note that this is not an I/O
!  * function.
!  */
! Datum
! to_regclass(PG_FUNCTION_ARGS)
! {
! 	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid		   result;
  
+ 	if (regclass_guts(class_name_or_oid, &result, true))
  		PG_RETURN_OID(result);
! 	else
! 		PG_RETURN_NULL();
  }
  
  /*
*************** Datum
*** 968,1036 ****
  regtypein(PG_FUNCTION_ARGS)
  {
  	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result = InvalidOid;
! 	int32		typmod;
! 
! 	/* '-' ? */
! 	if (strcmp(typ_name_or_oid, "-") == 0)
! 		PG_RETURN_OID(InvalidOid);
! 
! 	/* Numeric OID? */
! 	if (typ_name_or_oid[0] >= '0' &&
! 		typ_name_or_oid[0] <= '9' &&
! 		strspn(typ_name_or_oid, "0123456789") == strlen(typ_name_or_oid))
! 	{
! 		result = DatumGetObjectId(DirectFunctionCall1(oidin,
! 										  CStringGetDatum(typ_name_or_oid)));
! 		PG_RETURN_OID(result);
! 	}
! 
! 	/* Else it's a type name, possibly schema-qualified or decorated */
! 
! 	/*
! 	 * In bootstrap mode we assume the given name is not schema-qualified, and
! 	 * just search pg_type for a match.  This is needed for initializing other
! 	 * system catalogs (pg_namespace may not exist yet, and certainly there
! 	 * are no schemas other than pg_catalog).
! 	 */
! 	if (IsBootstrapProcessingMode())
! 	{
! 		Relation	hdesc;
! 		ScanKeyData skey[1];
! 		SysScanDesc sysscan;
! 		HeapTuple	tuple;
! 
! 		ScanKeyInit(&skey[0],
! 					Anum_pg_type_typname,
! 					BTEqualStrategyNumber, F_NAMEEQ,
! 					CStringGetDatum(typ_name_or_oid));
! 
! 		hdesc = heap_open(TypeRelationId, AccessShareLock);
! 		sysscan = systable_beginscan(hdesc, TypeNameNspIndexId, true,
! 									 NULL, 1, skey);
  
! 		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
! 			result = HeapTupleGetOid(tuple);
! 		else
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_OBJECT),
! 					 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
  
! 		/* We assume there can be only one match */
  
! 		systable_endscan(sysscan);
! 		heap_close(hdesc, AccessShareLock);
  
  		PG_RETURN_OID(result);
! 	}
! 
! 	/*
! 	 * Normal case: invoke the full parser to deal with special cases such as
! 	 * array syntax.
! 	 */
! 	parseTypeString(typ_name_or_oid, &result, &typmod);
! 
! 	PG_RETURN_OID(result);
  }
  
  /*
--- 806,838 ----
  regtypein(PG_FUNCTION_ARGS)
  {
  	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result;
  
! 	if (!regtype_guts(typ_name_or_oid, &result, false))
! 		ereport(ERROR,
! 				(errcode(ERRCODE_UNDEFINED_OBJECT),
! 				 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
  
! 	PG_RETURN_OID(result);
! }
  
! /*
!  * to_regtype		- converts "typename" to type OID
!  *
!  * This function differs from regtypein only in returning NULL and not raising
!  * an error when the typename is not found. Note that this is not an I/O
!  * function.
!  */
! Datum
! to_regtype(PG_FUNCTION_ARGS)
! {
! 	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
! 	Oid			result;
  
+ 	if (regtype_guts(typ_name_or_oid, &result, true))
  		PG_RETURN_OID(result);
! 	else
! 		PG_RETURN_NULL();
  }
  
  /*
*************** stringToQualifiedNameList(const char *st
*** 1388,1393 ****
--- 1190,1574 ----
   *****************************************************************************/
  
  /*
+  * Guts of regprocin and to_regproc.
+  * If the proname is found, returns true and the OID is stored into *proid_p.
+  * If not found and missing_ok is true, returns false instead of raising an
+  * error.
+  */
+ static bool
+ regproc_guts(char *pro_name_or_oid, RegProcedure *proid_p, bool missing_ok)
+ {
+ 	List	   *names;
+ 	FuncCandidateList clist;
+ 
+ 	*proid_p = InvalidOid;
+ 
+ 	/* '-' ? */
+ 	if (strcmp(pro_name_or_oid, "-") == 0)
+ 		return true;
+ 
+ 	/* Numeric OID? */
+ 	if (pro_name_or_oid[0] >= '0' &&
+ 		pro_name_or_oid[0] <= '9' &&
+ 		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
+ 	{
+ 		*proid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
+ 										  CStringGetDatum(pro_name_or_oid)));
+ 		return true;
+ 	}
+ 
+ 	/* Else it's a name, possibly schema-qualified */
+ 
+ 	/*
+ 	 * In bootstrap mode we assume the given name is not schema-qualified, and
+ 	 * just search pg_proc for a unique match.	This is needed for
+ 	 * initializing other system catalogs (pg_namespace may not exist yet, and
+ 	 * certainly there are no schemas other than pg_catalog).
+ 	 */
+ 	if (IsBootstrapProcessingMode())
+ 	{
+ 		int			matches = 0;
+ 		Relation	hdesc;
+ 		ScanKeyData skey[1];
+ 		SysScanDesc sysscan;
+ 		HeapTuple	tuple;
+ 
+ 		ScanKeyInit(&skey[0],
+ 					Anum_pg_proc_proname,
+ 					BTEqualStrategyNumber, F_NAMEEQ,
+ 					CStringGetDatum(pro_name_or_oid));
+ 
+ 		hdesc = heap_open(ProcedureRelationId, AccessShareLock);
+ 		sysscan = systable_beginscan(hdesc, ProcedureNameArgsNspIndexId, true,
+ 									 NULL, 1, skey);
+ 
+ 		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
+ 		{
+ 			*proid_p = (RegProcedure) HeapTupleGetOid(tuple);
+ 			if (++matches > 1)
+ 				break;
+ 		}
+ 
+ 		systable_endscan(sysscan);
+ 		heap_close(hdesc, AccessShareLock);
+ 
+ 		if (matches == 0)
+ 		{
+ 			if (!missing_ok)
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_UNDEFINED_FUNCTION),
+ 						 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
+ 			return false;
+ 		}
+ 		else if (matches > 1)
+ 		{
+ 			if (!missing_ok)
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
+ 						 errmsg("more than one function named \"%s\"",
+ 								pro_name_or_oid)));
+ 			return false;
+ 		}
+ 
+ 		return true;
+ 	}
+ 
+ 	/*
+ 	 * Normal case: parse the name into components and see if it matches any
+ 	 * pg_proc entries in the current search path.
+ 	 */
+ 	names = stringToQualifiedNameList(pro_name_or_oid);
+ 	clist = FuncnameGetCandidates(names, -1, NIL, false, false, missing_ok);
+ 
+ 	if (clist == NULL)
+ 	{
+ 		if (!missing_ok)
+ 			ereport(ERROR,
+ 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
+ 					 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
+ 		return false;
+ 	}
+ 	else if (clist->next != NULL)
+ 	{
+ 		if (!missing_ok)
+ 			ereport(ERROR,
+ 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
+ 					 errmsg("more than one function named \"%s\"",
+ 							pro_name_or_oid)));
+ 		return false;
+ 	}
+ 
+ 	*proid_p = clist->oid;
+ 
+ 	return true;
+ }
+ 
+ /*
+  * Guts of regoperin and to_regoper.
+  * If the operator is found, returns true and the OID is stored into *oprid_p.
+  * If not found and missing_ok is true, returns false instead of raising an
+  * error.
+  */
+ static bool
+ regoper_guts(char *opr_name_or_oid, Oid *oprid_p, bool missing_ok)
+ {
+ 	List	   *names;
+ 	FuncCandidateList clist;
+ 
+ 	*oprid_p = InvalidOid;
+ 
+ 	/* '0' ? */
+ 	if (strcmp(opr_name_or_oid, "0") == 0)
+ 		return true;
+ 
+ 	/* Numeric OID? */
+ 	if (opr_name_or_oid[0] >= '0' &&
+ 		opr_name_or_oid[0] <= '9' &&
+ 		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
+ 	{
+ 		*oprid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
+ 										  CStringGetDatum(opr_name_or_oid)));
+ 		return true;
+ 	}
+ 
+ 	/* Else it's a name, possibly schema-qualified */
+ 
+ 	/*
+ 	 * In bootstrap mode we assume the given name is not schema-qualified, and
+ 	 * just search pg_operator for a unique match.	This is needed for
+ 	 * initializing other system catalogs (pg_namespace may not exist yet, and
+ 	 * certainly there are no schemas other than pg_catalog).
+ 	 */
+ 	if (IsBootstrapProcessingMode())
+ 	{
+ 		int			matches = 0;
+ 		Relation	hdesc;
+ 		ScanKeyData skey[1];
+ 		SysScanDesc sysscan;
+ 		HeapTuple	tuple;
+ 
+ 		ScanKeyInit(&skey[0],
+ 					Anum_pg_operator_oprname,
+ 					BTEqualStrategyNumber, F_NAMEEQ,
+ 					CStringGetDatum(opr_name_or_oid));
+ 
+ 		hdesc = heap_open(OperatorRelationId, AccessShareLock);
+ 		sysscan = systable_beginscan(hdesc, OperatorNameNspIndexId, true,
+ 									 NULL, 1, skey);
+ 
+ 		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
+ 		{
+ 			*oprid_p = HeapTupleGetOid(tuple);
+ 			if (++matches > 1)
+ 				break;
+ 		}
+ 
+ 		systable_endscan(sysscan);
+ 		heap_close(hdesc, AccessShareLock);
+ 
+ 		if (matches == 0)
+ 		{
+ 			if (!missing_ok)
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_UNDEFINED_FUNCTION),
+ 						 errmsg("operator does not exist: %s", opr_name_or_oid)));
+ 			return false;
+ 		}
+ 		else if (matches > 1)
+ 		{
+ 			if (!missing_ok)
+ 				ereport(ERROR,
+ 						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
+ 						 errmsg("more than one operator named %s",
+ 								opr_name_or_oid)));
+ 			return false;
+ 		}
+ 
+ 		return true;
+ 	}
+ 
+ 	/*
+ 	 * Normal case: parse the name into components and see if it matches any
+ 	 * pg_operator entries in the current search path.
+ 	 */
+ 	names = stringToQualifiedNameList(opr_name_or_oid);
+ 	clist = OpernameGetCandidates(names, '\0', missing_ok);
+ 
+ 	if (clist == NULL)
+ 	{
+ 		if (!missing_ok)
+ 			ereport(ERROR,
+ 					(errcode(ERRCODE_UNDEFINED_FUNCTION),
+ 					 errmsg("operator does not exist: %s", opr_name_or_oid)));
+ 		return false;
+ 	}
+ 	else if (clist->next != NULL)
+ 	{
+ 		if (!missing_ok)
+ 			ereport(ERROR,
+ 					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
+ 					 errmsg("more than one operator named %s",
+ 							opr_name_or_oid)));
+ 		return false;
+ 	}
+ 
+ 	*oprid_p = clist->oid;
+ 
+ 	return true;
+ }
+ 
+ /*
+  * Guts of regclassin and to_regclass.
+  * If the classname is found, returns true and the OID is stored into *classid_p.
+  * If not found and missing_ok is true, or in bootstrap mode, returns false
+  * instead of raising an error
+  */
+ static bool
+ regclass_guts(char *class_name_or_oid, Oid *classid_p, bool missing_ok)
+ {
+ 	List	   *names;
+ 	bool		result = true;
+ 
+ 	*classid_p = InvalidOid;
+ 
+ 	/* '-' ? */
+ 	if (strcmp(class_name_or_oid, "-") == 0)
+ 		return true;
+ 
+ 	/* Numeric OID? */
+ 	if (class_name_or_oid[0] >= '0' &&
+ 		class_name_or_oid[0] <= '9' &&
+ 		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
+ 	{
+ 		*classid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
+ 										  CStringGetDatum(class_name_or_oid)));
+ 		return true;
+ 	}
+ 
+ 	/* Else it's a name, possibly schema-qualified */
+ 
+ 	/*
+ 	 * In bootstrap mode we assume the given name is not schema-qualified, and
+ 	 * just search pg_class for a match.  This is needed for initializing
+ 	 * other system catalogs (pg_namespace may not exist yet, and certainly
+ 	 * there are no schemas other than pg_catalog).
+ 	 */
+ 	if (IsBootstrapProcessingMode())
+ 	{
+ 		Relation	hdesc;
+ 		ScanKeyData skey[1];
+ 		SysScanDesc sysscan;
+ 		HeapTuple	tuple;
+ 
+ 		ScanKeyInit(&skey[0],
+ 					Anum_pg_class_relname,
+ 					BTEqualStrategyNumber, F_NAMEEQ,
+ 					CStringGetDatum(class_name_or_oid));
+ 
+ 		hdesc = heap_open(RelationRelationId, AccessShareLock);
+ 		sysscan = systable_beginscan(hdesc, ClassNameNspIndexId, true,
+ 									 NULL, 1, skey);
+ 
+ 		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
+ 			*classid_p = HeapTupleGetOid(tuple);
+ 		else
+ 			result = false;
+ 
+ 		/* We assume there can be only one match */
+ 
+ 		systable_endscan(sysscan);
+ 		heap_close(hdesc, AccessShareLock);
+ 
+ 		return result;
+ 	}
+ 
+ 	/*
+ 	 * Normal case: parse the name into components and see if it matches any
+ 	 * pg_class entries in the current search path.
+ 	 */
+ 	names = stringToQualifiedNameList(class_name_or_oid);
+ 
+ 	/* We might not even have permissions on this relation; don't lock it. */
+ 	*classid_p = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, missing_ok);
+ 
+ 	return OidIsValid(*classid_p);
+ }
+ 
+ /*
+  * Guts of regtypein and to_regtype.
+  * If the type is found, returns true and the OID is stored into *typid_p.
+  * If not found and missing_ok is true, or in bootstrap mode, returns false
+  * instead of raising an error
+  */
+ static bool
+ regtype_guts(char *typ_name_or_oid, Oid *typid_p, bool missing_ok)
+ {
+ 	int32		typmod;
+ 	bool		result = true;
+ 
+ 	*typid_p = InvalidOid;
+ 
+ 	/* '-' ? */
+ 	if (strcmp(typ_name_or_oid, "-") == 0)
+ 		return true;
+ 
+ 	/* Numeric OID? */
+ 	if (typ_name_or_oid[0] >= '0' &&
+ 		typ_name_or_oid[0] <= '9' &&
+ 		strspn(typ_name_or_oid, "0123456789") == strlen(typ_name_or_oid))
+ 	{
+ 		*typid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
+ 										  CStringGetDatum(typ_name_or_oid)));
+ 		return true;
+ 	}
+ 
+ 	/* Else it's a type name, possibly schema-qualified or decorated */
+ 
+ 	/*
+ 	 * In bootstrap mode we assume the given name is not schema-qualified, and
+ 	 * just search pg_type for a match.  This is needed for initializing other
+ 	 * system catalogs (pg_namespace may not exist yet, and certainly there
+ 	 * are no schemas other than pg_catalog).
+ 	 */
+ 	if (IsBootstrapProcessingMode())
+ 	{
+ 		Relation	hdesc;
+ 		ScanKeyData skey[1];
+ 		SysScanDesc sysscan;
+ 		HeapTuple	tuple;
+ 
+ 		ScanKeyInit(&skey[0],
+ 					Anum_pg_type_typname,
+ 					BTEqualStrategyNumber, F_NAMEEQ,
+ 					CStringGetDatum(typ_name_or_oid));
+ 
+ 		hdesc = heap_open(TypeRelationId, AccessShareLock);
+ 		sysscan = systable_beginscan(hdesc, TypeNameNspIndexId, true,
+ 									 NULL, 1, skey);
+ 
+ 		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
+ 			*typid_p = HeapTupleGetOid(tuple);
+ 		else
+ 			result = false;
+ 
+ 		/* We assume there can be only one match */
+ 
+ 		systable_endscan(sysscan);
+ 		heap_close(hdesc, AccessShareLock);
+ 
+ 		return result;
+ 	}
+ 
+ 	/*
+ 	 * Normal case: invoke the full parser to deal with special cases such as
+ 	 * array syntax.
+ 	 */
+ 	parseTypeString(typ_name_or_oid, typid_p, &typmod, missing_ok);
+ 
+ 	return OidIsValid(*typid_p);
+ }
+ 
+ /*
   * Given a C string, parse it into a qualified function or operator name
   * followed by a parenthesized list of type names.	Reduce the
   * type names to an array of OIDs (returned into *nargs and *argtypes;
*************** parseNameAndArgTypes(const char *string,
*** 1523,1529 ****
  		else
  		{
  			/* Use full parser to resolve the type name */
! 			parseTypeString(typename, &typeid, &typmod);
  		}
  		if (*nargs >= FUNC_MAX_ARGS)
  			ereport(ERROR,
--- 1704,1710 ----
  		else
  		{
  			/* Use full parser to resolve the type name */
! 			parseTypeString(typename, &typeid, &typmod, false);
  		}
  		if (*nargs >= FUNC_MAX_ARGS)
  			ereport(ERROR,
diff --git a/src/include/catalog/namespace.h b/src/include/catalog/namespace.h
new file mode 100644
index b30e5e8..2f9d391
*** a/src/include/catalog/namespace.h
--- b/src/include/catalog/namespace.h
*************** extern FuncCandidateList FuncnameGetCand
*** 76,82 ****
  extern bool FunctionIsVisible(Oid funcid);
  
  extern Oid	OpernameGetOprid(List *names, Oid oprleft, Oid oprright);
! extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind);
  extern bool OperatorIsVisible(Oid oprid);
  
  extern Oid	OpclassnameGetOpcid(Oid amid, const char *opcname);
--- 76,83 ----
  extern bool FunctionIsVisible(Oid funcid);
  
  extern Oid	OpernameGetOprid(List *names, Oid oprleft, Oid oprright);
! extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind,
! 					  bool missing_schema_ok);
  extern bool OperatorIsVisible(Oid oprid);
  
  extern Oid	OpclassnameGetOpcid(Oid amid, const char *opcname);
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
new file mode 100644
index 334e6b8..21c17a0
*** a/src/include/catalog/pg_proc.h
--- b/src/include/catalog/pg_proc.h
*************** DATA(insert OID =  44 (  regprocin		   P
*** 173,178 ****
--- 173,180 ----
  DESCR("I/O");
  DATA(insert OID =  45 (  regprocout		   PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "24" _null_ _null_ _null_ _null_ regprocout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3494 (  to_regproc		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 24 "2275" _null_ _null_ _null_ _null_ to_regproc _null_ _null_ _null_ ));
+ DESCR("convert proname to regproc");
  DATA(insert OID =  46 (  textin			   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 25 "2275" _null_ _null_ _null_ _null_ textin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID =  47 (  textout		   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2275 "25" _null_ _null_ _null_ _null_ textout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2214 (  regoperin			PG
*** 3304,3309 ****
--- 3306,3313 ----
  DESCR("I/O");
  DATA(insert OID = 2215 (  regoperout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2203" _null_ _null_ _null_ _null_ regoperout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3492 (  to_regoper		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2203 "2275" _null_ _null_ _null_ _null_ to_regoper _null_ _null_ _null_ ));
+ DESCR("convert operator name to regoper");
  DATA(insert OID = 2216 (  regoperatorin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2204 "2275" _null_ _null_ _null_ _null_ regoperatorin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2217 (  regoperatorout	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2204" _null_ _null_ _null_ _null_ regoperatorout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2218 (  regclassin		PG
*** 3312,3321 ****
--- 3316,3329 ----
  DESCR("I/O");
  DATA(insert OID = 2219 (  regclassout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2205" _null_ _null_ _null_ _null_ regclassout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3495 (  to_regclass		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "2275" _null_ _null_ _null_ _null_ to_regclass _null_ _null_ _null_ ));
+ DESCR("convert classname to regclass");
  DATA(insert OID = 2220 (  regtypein			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ regtypein _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2221 (  regtypeout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2206" _null_ _null_ _null_ _null_ regtypeout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3493 (  to_regtype		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ to_regtype _null_ _null_ _null_ ));
+ DESCR("convert type name to regtype");
  DATA(insert OID = 1079 (  regclass			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "25" _null_ _null_ _null_ _null_	text_regclass _null_ _null_ _null_ ));
  DESCR("convert text to regclass");
  
diff --git a/src/include/parser/parse_type.h b/src/include/parser/parse_type.h
new file mode 100644
index ab73148..fa9cc59
*** a/src/include/parser/parse_type.h
--- b/src/include/parser/parse_type.h
*************** extern Datum stringTypeDatum(Type tp, ch
*** 47,53 ****
  
  extern Oid	typeidTypeRelid(Oid type_id);
  
! extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p);
  
  #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
  
--- 47,53 ----
  
  extern Oid	typeidTypeRelid(Oid type_id);
  
! extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p, bool missing_ok);
  
  #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
  
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
new file mode 100644
index 031a43a..720c831
*** a/src/include/utils/builtins.h
--- b/src/include/utils/builtins.h
*************** extern char *regexp_fixed_prefix(text *t
*** 597,602 ****
--- 597,603 ----
  /* regproc.c */
  extern Datum regprocin(PG_FUNCTION_ARGS);
  extern Datum regprocout(PG_FUNCTION_ARGS);
+ extern Datum to_regproc(PG_FUNCTION_ARGS);
  extern Datum regprocrecv(PG_FUNCTION_ARGS);
  extern Datum regprocsend(PG_FUNCTION_ARGS);
  extern Datum regprocedurein(PG_FUNCTION_ARGS);
*************** extern Datum regoperin(PG_FUNCTION_ARGS)
*** 607,612 ****
--- 608,614 ----
  extern Datum regoperout(PG_FUNCTION_ARGS);
  extern Datum regoperrecv(PG_FUNCTION_ARGS);
  extern Datum regopersend(PG_FUNCTION_ARGS);
+ extern Datum to_regoper(PG_FUNCTION_ARGS);
  extern Datum regoperatorin(PG_FUNCTION_ARGS);
  extern Datum regoperatorout(PG_FUNCTION_ARGS);
  extern Datum regoperatorrecv(PG_FUNCTION_ARGS);
*************** extern Datum regclassin(PG_FUNCTION_ARGS
*** 615,624 ****
--- 617,628 ----
  extern Datum regclassout(PG_FUNCTION_ARGS);
  extern Datum regclassrecv(PG_FUNCTION_ARGS);
  extern Datum regclasssend(PG_FUNCTION_ARGS);
+ extern Datum to_regclass(PG_FUNCTION_ARGS);
  extern Datum regtypein(PG_FUNCTION_ARGS);
  extern Datum regtypeout(PG_FUNCTION_ARGS);
  extern Datum regtyperecv(PG_FUNCTION_ARGS);
  extern Datum regtypesend(PG_FUNCTION_ARGS);
+ extern Datum to_regtype(PG_FUNCTION_ARGS);
  extern Datum regconfigin(PG_FUNCTION_ARGS);
  extern Datum regconfigout(PG_FUNCTION_ARGS);
  extern Datum regconfigrecv(PG_FUNCTION_ARGS);
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
new file mode 100644
index 7bc29a6..5fff635
*** a/src/pl/plperl/plperl.c
--- b/src/pl/plperl/plperl.c
*************** plperl_spi_prepare(char *query, int argc
*** 3420,3426 ****
  			char	   *typstr;
  
  			typstr = sv2cstr(argv[i]);
! 			parseTypeString(typstr, &typId, &typmod);
  			pfree(typstr);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
--- 3420,3426 ----
  			char	   *typstr;
  
  			typstr = sv2cstr(argv[i]);
! 			parseTypeString(typstr, &typId, &typmod, false);
  			pfree(typstr);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
new file mode 100644
index c0cb585..1862293
*** a/src/pl/plpgsql/src/pl_gram.y
--- b/src/pl/plpgsql/src/pl_gram.y
*************** parse_datatype(const char *string, int l
*** 3462,3468 ****
  	error_context_stack = &syntax_errcontext;
  
  	/* Let the main parser try to parse it under standard SQL rules */
! 	parseTypeString(string, &type_id, &typmod);
  
  	/* Restore former ereport callback */
  	error_context_stack = syntax_errcontext.previous;
--- 3462,3468 ----
  	error_context_stack = &syntax_errcontext;
  
  	/* Let the main parser try to parse it under standard SQL rules */
! 	parseTypeString(string, &type_id, &typmod, false);
  
  	/* Restore former ereport callback */
  	error_context_stack = syntax_errcontext.previous;
diff --git a/src/pl/plpython/plpy_spi.c b/src/pl/plpython/plpy_spi.c
new file mode 100644
index 982bf84..060d514
*** a/src/pl/plpython/plpy_spi.c
--- b/src/pl/plpython/plpy_spi.c
*************** PLy_spi_prepare(PyObject *self, PyObject
*** 113,119 ****
  			 *information for input conversion.
  			 ********************************************************/
  
! 			parseTypeString(sptr, &typeId, &typmod);
  
  			typeTup = SearchSysCache1(TYPEOID,
  									  ObjectIdGetDatum(typeId));
--- 113,119 ----
  			 *information for input conversion.
  			 ********************************************************/
  
! 			parseTypeString(sptr, &typeId, &typmod, false);
  
  			typeTup = SearchSysCache1(TYPEOID,
  									  ObjectIdGetDatum(typeId));
diff --git a/src/pl/tcl/pltcl.c b/src/pl/tcl/pltcl.c
new file mode 100644
index b3bf65e..2d862a6
*** a/src/pl/tcl/pltcl.c
--- b/src/pl/tcl/pltcl.c
*************** pltcl_SPI_prepare(ClientData cdata, Tcl_
*** 2165,2171 ****
  						typIOParam;
  			int32		typmod;
  
! 			parseTypeString(args[i], &typId, &typmod);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
  
--- 2165,2171 ----
  						typIOParam;
  			int32		typmod;
  
! 			parseTypeString(args[i], &typId, &typmod, false);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
  
diff --git a/src/test/regress/expected/regproc.out b/src/test/regress/expected/regproc.out
new file mode 100644
index ...9f8d8e8
*** a/src/test/regress/expected/regproc.out
--- b/src/test/regress/expected/regproc.out
***************
*** 0 ****
--- 1,237 ----
+ --
+ -- regproc
+ --
+ /* If objects exist, return oids */
+ -- without schemaname
+ SELECT regoper('||/');
+  regoper 
+ ---------
+  ||/
+ (1 row)
+ 
+ SELECT regproc('now');
+  regproc 
+ ---------
+  now
+ (1 row)
+ 
+ SELECT regclass('pg_class');
+  regclass 
+ ----------
+  pg_class
+ (1 row)
+ 
+ SELECT regtype('int4');
+  regtype 
+ ---------
+  integer
+ (1 row)
+ 
+ SELECT to_regoper('||/');
+  to_regoper 
+ ------------
+  ||/
+ (1 row)
+ 
+ SELECT to_regproc('now');
+  to_regproc 
+ ------------
+  now
+ (1 row)
+ 
+ SELECT to_regclass('pg_class');
+  to_regclass 
+ -------------
+  pg_class
+ (1 row)
+ 
+ SELECT to_regtype('int4');
+  to_regtype 
+ ------------
+  integer
+ (1 row)
+ 
+ -- with schemaname
+ SELECT regoper('pg_catalog.||/');
+  regoper 
+ ---------
+  ||/
+ (1 row)
+ 
+ SELECT regproc('pg_catalog.now');
+  regproc 
+ ---------
+  now
+ (1 row)
+ 
+ SELECT regclass('pg_catalog.pg_class');
+  regclass 
+ ----------
+  pg_class
+ (1 row)
+ 
+ SELECT regtype('pg_catalog.int4');
+  regtype 
+ ---------
+  integer
+ (1 row)
+ 
+ SELECT to_regoper('pg_catalog.||/');
+  to_regoper 
+ ------------
+  ||/
+ (1 row)
+ 
+ SELECT to_regproc('pg_catalog.now');
+  to_regproc 
+ ------------
+  now
+ (1 row)
+ 
+ SELECT to_regclass('pg_catalog.pg_class');
+  to_regclass 
+ -------------
+  pg_class
+ (1 row)
+ 
+ SELECT to_regtype('pg_catalog.int4');
+  to_regtype 
+ ------------
+  integer
+ (1 row)
+ 
+ /* If objects don't exist, raise errors. */
+ -- without schemaname
+ SELECT regoper('||//');
+ ERROR:  operator does not exist: ||//
+ LINE 3: SELECT regoper('||//');
+                        ^
+ SELECT regproc('know');
+ ERROR:  function "know" does not exist
+ LINE 1: SELECT regproc('know');
+                        ^
+ SELECT regclass('pg_classes');
+ ERROR:  relation "pg_classes" does not exist
+ LINE 1: SELECT regclass('pg_classes');
+                         ^
+ SELECT regtype('int3');
+ ERROR:  type "int3" does not exist
+ LINE 1: SELECT regtype('int3');
+                        ^
+ -- with schemaname
+ SELECT regoper('ng_catalog.||/');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regoper('ng_catalog.||/');
+                        ^
+ SELECT regproc('ng_catalog.now');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regproc('ng_catalog.now');
+                        ^
+ SELECT regclass('ng_catalog.pg_class');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regclass('ng_catalog.pg_class');
+                         ^
+ SELECT regtype('ng_catalog.int4');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regtype('ng_catalog.int4');
+                        ^
+ /* If objects don't exist, return NULL with no error. */
+ -- without schemaname
+ SELECT to_regoper('||//');
+  to_regoper 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regproc('know');
+  to_regproc 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regclass('pg_classes');
+  to_regclass 
+ -------------
+  
+ (1 row)
+ 
+ SELECT to_regtype('int3');
+  to_regtype 
+ ------------
+  
+ (1 row)
+ 
+ -- with schemaname
+ SELECT to_regoper('ng_catalog.||/');
+  to_regoper 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regproc('ng_catalog.now');
+  to_regproc 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regclass('ng_catalog.pg_class');
+  to_regclass 
+ -------------
+  
+ (1 row)
+ 
+ SELECT to_regtype('ng_catalog.int4');
+  to_regtype 
+ ------------
+  
+ (1 row)
+ 
+ /* Cast 0 to InvalidOid */
+ SELECT regoper('0');
+  regoper 
+ ---------
+  0
+ (1 row)
+ 
+ SELECT regproc('0');
+  regproc 
+ ---------
+  -
+ (1 row)
+ 
+ SELECT regclass('0');
+  regclass 
+ ----------
+  -
+ (1 row)
+ 
+ SELECT regtype('0');
+  regtype 
+ ---------
+  -
+ (1 row)
+ 
+ SELECT to_regoper('0');
+  to_regoper 
+ ------------
+  0
+ (1 row)
+ 
+ SELECT to_regproc('0');
+  to_regproc 
+ ------------
+  -
+ (1 row)
+ 
+ SELECT to_regclass('0');
+  to_regclass 
+ -------------
+  -
+ (1 row)
+ 
+ SELECT to_regtype('0');
+  to_regtype 
+ ------------
+  -
+ (1 row)
+ 
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
new file mode 100644
index c62be2a..c0416f4
*** a/src/test/regress/parallel_schedule
--- b/src/test/regress/parallel_schedule
*************** test: tablespace
*** 13,19 ****
  # ----------
  # The first group of parallel tests
  # ----------
! test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes pg_lsn
  
  # Depends on things setup during char, varchar and text
  test: strings
--- 13,19 ----
  # ----------
  # The first group of parallel tests
  # ----------
! test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes pg_lsn regproc
  
  # Depends on things setup during char, varchar and text
  test: strings
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
new file mode 100644
index 885ca9a..16a1905
*** a/src/test/regress/serial_schedule
--- b/src/test/regress/serial_schedule
*************** test: enum
*** 20,25 ****
--- 20,26 ----
  test: money
  test: rangetypes
  test: pg_lsn
+ test: regproc
  test: strings
  test: numerology
  test: point
diff --git a/src/test/regress/sql/regproc.sql b/src/test/regress/sql/regproc.sql
new file mode 100644
index ...3cfa726
*** a/src/test/regress/sql/regproc.sql
--- b/src/test/regress/sql/regproc.sql
***************
*** 0 ****
--- 1,74 ----
+ --
+ -- regproc
+ --
+ 
+ /* If objects exist, return oids */
+ 
+ -- without schemaname
+ 
+ SELECT regoper('||/');
+ SELECT regproc('now');
+ SELECT regclass('pg_class');
+ SELECT regtype('int4');
+ 
+ SELECT to_regoper('||/');
+ SELECT to_regproc('now');
+ SELECT to_regclass('pg_class');
+ SELECT to_regtype('int4');
+ 
+ -- with schemaname
+ 
+ SELECT regoper('pg_catalog.||/');
+ SELECT regproc('pg_catalog.now');
+ SELECT regclass('pg_catalog.pg_class');
+ SELECT regtype('pg_catalog.int4');
+ 
+ SELECT to_regoper('pg_catalog.||/');
+ SELECT to_regproc('pg_catalog.now');
+ SELECT to_regclass('pg_catalog.pg_class');
+ SELECT to_regtype('pg_catalog.int4');
+ 
+ /* If objects don't exist, raise errors. */
+ 
+ -- without schemaname
+ 
+ SELECT regoper('||//');
+ SELECT regproc('know');
+ SELECT regclass('pg_classes');
+ SELECT regtype('int3');
+ 
+ -- with schemaname
+ 
+ SELECT regoper('ng_catalog.||/');
+ SELECT regproc('ng_catalog.now');
+ SELECT regclass('ng_catalog.pg_class');
+ SELECT regtype('ng_catalog.int4');
+ 
+ /* If objects don't exist, return NULL with no error. */
+ 
+ -- without schemaname
+ 
+ SELECT to_regoper('||//');
+ SELECT to_regproc('know');
+ SELECT to_regclass('pg_classes');
+ SELECT to_regtype('int3');
+ 
+ -- with schemaname
+ 
+ SELECT to_regoper('ng_catalog.||/');
+ SELECT to_regproc('ng_catalog.now');
+ SELECT to_regclass('ng_catalog.pg_class');
+ SELECT to_regtype('ng_catalog.int4');
+ 
+ /* Cast 0 to InvalidOid */
+ 
+ SELECT regoper('0');
+ SELECT regproc('0');
+ SELECT regclass('0');
+ SELECT regtype('0');
+ 
+ SELECT to_regoper('0');
+ SELECT to_regproc('0');
+ SELECT to_regclass('0');
+ SELECT to_regtype('0');
+ 

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 6e2fbda..11689f9 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -15279,6 +15279,22 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
     <primary>collation for</primary>
    </indexterm>
 
+   <indexterm>
+    <primary>to_regclass</primary>
+   </indexterm>
+
+   <indexterm>
+    <primary>to_regproc</primary>
+   </indexterm>
+
+   <indexterm>
+    <primary>to_regoper</primary>
+   </indexterm>
+
+   <indexterm>
+    <primary>to_regtype</primary>
+   </indexterm>
+
   <para>
    <xref linkend="functions-info-catalog-table"> lists functions that
    extract information from the system catalogs.
@@ -15449,6 +15465,26 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
        <entry><type>text</type></entry>
        <entry>get the collation of the argument</entry>
       </row>
+      <row>
+       <entry><literal><function>to_regclass(<parameter>rel_name</parameter>)</function></literal></entry>
+       <entry><type>regclass</type></entry>
+       <entry>get the oid of the named relation</entry>
+      </row>
+      <row>
+       <entry><literal><function>to_regproc(<parameter>func_name</parameter>)</function></literal></entry>
+       <entry><type>regproc</type></entry>
+       <entry>get the oid of the named function</entry>
+      </row>
+      <row>
+       <entry><literal><function>to_regoper(<parameter>operator_name</parameter>)</function></literal></entry>
+       <entry><type>regoper</type></entry>
+       <entry>get the oid of the named operator</entry>
+      </row>
+      <row>
+       <entry><literal><function>to_regtype(<parameter>type_name</parameter>)</function></literal></entry>
+       <entry><type>regtype</type></entry>
+       <entry>get the oid of the named type</entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -15614,6 +15650,17 @@ SELECT collation for ('foo' COLLATE "de_DE");
   is not of a collatable data type, then an error is raised.
   </para>
 
+  <para>
+   The <function>to_regclass</function>, <function>to_regproc</function>,
+   <function>to_regoper</function> and <function>to_regtype</function>
+   work like casts to <type>regclass</>, <type>regproc</>, <type>regoper</> and
+   <type>regtype</>, respectively, except that they return NULL when no
+   object by that name is found, or in the case of
+   <function>to_regproc</function> and <function>to_regoper</function>
+   when more than one object with that name is found, rather than raising
+   an error.
+  </para>
+
    <indexterm>
     <primary>col_description</primary>
    </indexterm>
diff --git a/src/backend/catalog/namespace.c b/src/backend/catalog/namespace.c
index 6c2a5d2..5bf6d28 100644
--- a/src/backend/catalog/namespace.c
+++ b/src/backend/catalog/namespace.c
@@ -1556,7 +1556,7 @@ OpernameGetOprid(List *names, Oid oprleft, Oid oprright)
  * will be InvalidOid for a prefix or postfix oprkind.	nargs is 2, too.
  */
 FuncCandidateList
-OpernameGetCandidates(List *names, char oprkind)
+OpernameGetCandidates(List *names, char oprkind, bool missing_schema_ok)
 {
 	FuncCandidateList resultList = NULL;
 	char	   *resultSpace = NULL;
@@ -1573,7 +1573,9 @@ OpernameGetCandidates(List *names, char oprkind)
 	if (schemaname)
 	{
 		/* use exact schema given */
-		namespaceId = LookupExplicitNamespace(schemaname, false);
+		namespaceId = LookupExplicitNamespace(schemaname, missing_schema_ok);
+		if (missing_schema_ok && !OidIsValid(namespaceId))
+			return NULL;
 	}
 	else
 	{
diff --git a/src/backend/parser/parse_oper.c b/src/backend/parser/parse_oper.c
index 99dbd30..a2b712d 100644
--- a/src/backend/parser/parse_oper.c
+++ b/src/backend/parser/parse_oper.c
@@ -407,7 +407,7 @@ oper(ParseState *pstate, List *opname, Oid ltypeId, Oid rtypeId,
 		FuncCandidateList clist;
 
 		/* Get binary operators of given name */
-		clist = OpernameGetCandidates(opname, 'b');
+		clist = OpernameGetCandidates(opname, 'b', false);
 
 		/* No operators found? Then fail... */
 		if (clist != NULL)
@@ -553,7 +553,7 @@ right_oper(ParseState *pstate, List *op, Oid arg, bool noError, int location)
 		FuncCandidateList clist;
 
 		/* Get postfix operators of given name */
-		clist = OpernameGetCandidates(op, 'r');
+		clist = OpernameGetCandidates(op, 'r', false);
 
 		/* No operators found? Then fail... */
 		if (clist != NULL)
@@ -631,7 +631,7 @@ left_oper(ParseState *pstate, List *op, Oid arg, bool noError, int location)
 		FuncCandidateList clist;
 
 		/* Get prefix operators of given name */
-		clist = OpernameGetCandidates(op, 'l');
+		clist = OpernameGetCandidates(op, 'l', false);
 
 		/* No operators found? Then fail... */
 		if (clist != NULL)
diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
index b329dfb..28aae59 100644
--- a/src/backend/parser/parse_type.c
+++ b/src/backend/parser/parse_type.c
@@ -706,9 +706,12 @@ pts_error_callback(void *arg)
  * Given a string that is supposed to be a SQL-compatible type declaration,
  * such as "int4" or "integer" or "character varying(32)", parse
  * the string and convert it to a type OID and type modifier.
+ * If the type name is not found, return InvalidOid if missing_ok
+ * = true, otherwise raise an error.
  */
 void
-parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p)
+parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p,
+				bool missing_ok)
 {
 	StringInfoData buf;
 	List	   *raw_parsetree_list;
@@ -717,6 +720,7 @@ parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p)
 	TypeCast   *typecast;
 	TypeName   *typeName;
 	ErrorContextCallback ptserrcontext;
+	Type		tup;
 
 	/* make sure we give useful error for empty input */
 	if (strspn(str, " \t\n\r\f") == strlen(str))
@@ -782,7 +786,28 @@ parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p)
 	if (typeName->setof)
 		goto fail;
 
-	typenameTypeIdAndMod(NULL, typeName, typeid_p, typmod_p);
+	tup = LookupTypeName(NULL, typeName, typmod_p, missing_ok);
+	if (tup == NULL)
+	{
+		if (!missing_ok)
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_OBJECT),
+					errmsg("type \"%s\" does not exist",
+							TypeNameToString(typeName)),
+					parser_errposition(NULL, typeName->location)));
+		*typeid_p = InvalidOid;
+	}
+	else
+	{
+		if (!((Form_pg_type) GETSTRUCT(tup))->typisdefined)
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_OBJECT),
+					errmsg("type \"%s\" is only a shell",
+							TypeNameToString(typeName)),
+					parser_errposition(NULL, typeName->location)));
+		*typeid_p = HeapTupleGetOid(tup);
+		ReleaseSysCache(tup);
+	}
 
 	pfree(buf.data);
 
diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
index 5d73562..08f116e 100644
--- a/src/backend/utils/adt/regproc.c
+++ b/src/backend/utils/adt/regproc.c
@@ -45,6 +45,10 @@ static char *format_operator_internal(Oid operator_oid, bool force_qualify);
 static char *format_procedure_internal(Oid procedure_oid, bool force_qualify);
 static void parseNameAndArgTypes(const char *string, bool allowNone,
 					 List **names, int *nargs, Oid *argtypes);
+static bool regproc_guts(char *pro_name_or_oid, Oid *proid_p, bool missing_ok);
+static bool regoper_guts(char *opr_name_or_oid, RegProcedure *oprid_p, bool missing_ok);
+static bool regclass_guts(char *class_name_or_oid, Oid *classid_p, bool missing_ok);
+static bool regtype_guts(char *typ_name_or_oid, Oid *typid_p, bool missing_ok);
 
 
 /*****************************************************************************
@@ -63,93 +67,29 @@ Datum
 regprocin(PG_FUNCTION_ARGS)
 {
 	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
-	RegProcedure result = InvalidOid;
-	List	   *names;
-	FuncCandidateList clist;
-
-	/* '-' ? */
-	if (strcmp(pro_name_or_oid, "-") == 0)
-		PG_RETURN_OID(InvalidOid);
-
-	/* Numeric OID? */
-	if (pro_name_or_oid[0] >= '0' &&
-		pro_name_or_oid[0] <= '9' &&
-		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
-	{
-		result = DatumGetObjectId(DirectFunctionCall1(oidin,
-										  CStringGetDatum(pro_name_or_oid)));
-		PG_RETURN_OID(result);
-	}
-
-	/* Else it's a name, possibly schema-qualified */
-
-	/*
-	 * In bootstrap mode we assume the given name is not schema-qualified, and
-	 * just search pg_proc for a unique match.	This is needed for
-	 * initializing other system catalogs (pg_namespace may not exist yet, and
-	 * certainly there are no schemas other than pg_catalog).
-	 */
-	if (IsBootstrapProcessingMode())
-	{
-		int			matches = 0;
-		Relation	hdesc;
-		ScanKeyData skey[1];
-		SysScanDesc sysscan;
-		HeapTuple	tuple;
-
-		ScanKeyInit(&skey[0],
-					Anum_pg_proc_proname,
-					BTEqualStrategyNumber, F_NAMEEQ,
-					CStringGetDatum(pro_name_or_oid));
-
-		hdesc = heap_open(ProcedureRelationId, AccessShareLock);
-		sysscan = systable_beginscan(hdesc, ProcedureNameArgsNspIndexId, true,
-									 NULL, 1, skey);
-
-		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
-		{
-			result = (RegProcedure) HeapTupleGetOid(tuple);
-			if (++matches > 1)
-				break;
-		}
+	RegProcedure result;
 
-		systable_endscan(sysscan);
-		heap_close(hdesc, AccessShareLock);
-
-		if (matches == 0)
-			ereport(ERROR,
-					(errcode(ERRCODE_UNDEFINED_FUNCTION),
-				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
+	regproc_guts(pro_name_or_oid, &result, false);
+	PG_RETURN_OID(result);
+}
 
-		else if (matches > 1)
-			ereport(ERROR,
-					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
-					 errmsg("more than one function named \"%s\"",
-							pro_name_or_oid)));
+/*
+ * to_regproc	- converts "proname" to proc OID
+ *
+ * This function differs from regprocin only in returning NULL and not raising
+ * an error when the proname is not found or more than one proname is found.
+ * Note that this is not an I/O function.
+ */
+Datum
+to_regproc(PG_FUNCTION_ARGS)
+{
+	char	   *pro_name_or_oid = PG_GETARG_CSTRING(0);
+	RegProcedure result;
 
+	if (regproc_guts(pro_name_or_oid, &result, true))
 		PG_RETURN_OID(result);
-	}
-
-	/*
-	 * Normal case: parse the name into components and see if it matches any
-	 * pg_proc entries in the current search path.
-	 */
-	names = stringToQualifiedNameList(pro_name_or_oid);
-	clist = FuncnameGetCandidates(names, -1, NIL, false, false, false);
-
-	if (clist == NULL)
-		ereport(ERROR,
-				(errcode(ERRCODE_UNDEFINED_FUNCTION),
-				 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
-	else if (clist->next != NULL)
-		ereport(ERROR,
-				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
-				 errmsg("more than one function named \"%s\"",
-						pro_name_or_oid)));
-
-	result = clist->oid;
-
-	PG_RETURN_OID(result);
+	else
+		PG_RETURN_NULL();
 }
 
 /*
@@ -431,92 +371,29 @@ Datum
 regoperin(PG_FUNCTION_ARGS)
 {
 	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
-	Oid			result = InvalidOid;
-	List	   *names;
-	FuncCandidateList clist;
-
-	/* '0' ? */
-	if (strcmp(opr_name_or_oid, "0") == 0)
-		PG_RETURN_OID(InvalidOid);
-
-	/* Numeric OID? */
-	if (opr_name_or_oid[0] >= '0' &&
-		opr_name_or_oid[0] <= '9' &&
-		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
-	{
-		result = DatumGetObjectId(DirectFunctionCall1(oidin,
-										  CStringGetDatum(opr_name_or_oid)));
-		PG_RETURN_OID(result);
-	}
-
-	/* Else it's a name, possibly schema-qualified */
-
-	/*
-	 * In bootstrap mode we assume the given name is not schema-qualified, and
-	 * just search pg_operator for a unique match.	This is needed for
-	 * initializing other system catalogs (pg_namespace may not exist yet, and
-	 * certainly there are no schemas other than pg_catalog).
-	 */
-	if (IsBootstrapProcessingMode())
-	{
-		int			matches = 0;
-		Relation	hdesc;
-		ScanKeyData skey[1];
-		SysScanDesc sysscan;
-		HeapTuple	tuple;
-
-		ScanKeyInit(&skey[0],
-					Anum_pg_operator_oprname,
-					BTEqualStrategyNumber, F_NAMEEQ,
-					CStringGetDatum(opr_name_or_oid));
-
-		hdesc = heap_open(OperatorRelationId, AccessShareLock);
-		sysscan = systable_beginscan(hdesc, OperatorNameNspIndexId, true,
-									 NULL, 1, skey);
-
-		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
-		{
-			result = HeapTupleGetOid(tuple);
-			if (++matches > 1)
-				break;
-		}
+	Oid			result;
 
-		systable_endscan(sysscan);
-		heap_close(hdesc, AccessShareLock);
+	regoper_guts(opr_name_or_oid, &result, false);
+	PG_RETURN_OID(result);
+}
 
-		if (matches == 0)
-			ereport(ERROR,
-					(errcode(ERRCODE_UNDEFINED_FUNCTION),
-					 errmsg("operator does not exist: %s", opr_name_or_oid)));
-		else if (matches > 1)
-			ereport(ERROR,
-					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
-					 errmsg("more than one operator named %s",
-							opr_name_or_oid)));
+/*
+ * to_regoper		- converts "oprname" to operator OID
+ *
+ * This function differs from regoperin only in returning NULL and not raising
+ * an error when the opername is not found or more than one opername is found.
+ * Note that this is not an I/O function.
+ */
+Datum
+to_regoper(PG_FUNCTION_ARGS)
+{
+	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
+	Oid			result;
 
+	if (regoper_guts(opr_name_or_oid, &result, true))
 		PG_RETURN_OID(result);
-	}
-
-	/*
-	 * Normal case: parse the name into components and see if it matches any
-	 * pg_operator entries in the current search path.
-	 */
-	names = stringToQualifiedNameList(opr_name_or_oid);
-	clist = OpernameGetCandidates(names, '\0');
-
-	if (clist == NULL)
-		ereport(ERROR,
-				(errcode(ERRCODE_UNDEFINED_FUNCTION),
-				 errmsg("operator does not exist: %s", opr_name_or_oid)));
-	else if (clist->next != NULL)
-		ereport(ERROR,
-				(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
-				 errmsg("more than one operator named %s",
-						opr_name_or_oid)));
-
-	result = clist->oid;
-
-	PG_RETURN_OID(result);
+	else
+		PG_RETURN_NULL();
 }
 
 /*
@@ -558,7 +435,7 @@ regoperout(PG_FUNCTION_ARGS)
 			 * qualify it.
 			 */
 			clist = OpernameGetCandidates(list_make1(makeString(oprname)),
-										  '\0');
+										  '\0', false);
 			if (clist != NULL && clist->next == NULL &&
 				clist->oid == oprid)
 				result = pstrdup(oprname);
@@ -804,72 +681,33 @@ Datum
 regclassin(PG_FUNCTION_ARGS)
 {
 	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
-	Oid			result = InvalidOid;
-	List	   *names;
-
-	/* '-' ? */
-	if (strcmp(class_name_or_oid, "-") == 0)
-		PG_RETURN_OID(InvalidOid);
-
-	/* Numeric OID? */
-	if (class_name_or_oid[0] >= '0' &&
-		class_name_or_oid[0] <= '9' &&
-		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
-	{
-		result = DatumGetObjectId(DirectFunctionCall1(oidin,
-										CStringGetDatum(class_name_or_oid)));
-		PG_RETURN_OID(result);
-	}
-
-	/* Else it's a name, possibly schema-qualified */
-
-	/*
-	 * In bootstrap mode we assume the given name is not schema-qualified, and
-	 * just search pg_class for a match.  This is needed for initializing
-	 * other system catalogs (pg_namespace may not exist yet, and certainly
-	 * there are no schemas other than pg_catalog).
-	 */
-	if (IsBootstrapProcessingMode())
-	{
-		Relation	hdesc;
-		ScanKeyData skey[1];
-		SysScanDesc sysscan;
-		HeapTuple	tuple;
-
-		ScanKeyInit(&skey[0],
-					Anum_pg_class_relname,
-					BTEqualStrategyNumber, F_NAMEEQ,
-					CStringGetDatum(class_name_or_oid));
-
-		hdesc = heap_open(RelationRelationId, AccessShareLock);
-		sysscan = systable_beginscan(hdesc, ClassNameNspIndexId, true,
-									 NULL, 1, skey);
+	Oid			result;
 
-		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
-			result = HeapTupleGetOid(tuple);
-		else
-			ereport(ERROR,
-					(errcode(ERRCODE_UNDEFINED_TABLE),
-			   errmsg("relation \"%s\" does not exist", class_name_or_oid)));
+	if (!regclass_guts(class_name_or_oid, &result, false))
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_TABLE),
+				 errmsg("relation \"%s\" does not exist", class_name_or_oid)));
 
-		/* We assume there can be only one match */
+	PG_RETURN_OID(result);
+}
 
-		systable_endscan(sysscan);
-		heap_close(hdesc, AccessShareLock);
+/*
+ * to_regclass		- converts "classname" to class OID
+ *
+ * This function differs from regclassin only in returning NULL and not raising
+ * an error when the classname is not found. Note that this is not an I/O
+ * function.
+ */
+Datum
+to_regclass(PG_FUNCTION_ARGS)
+{
+	char	   *class_name_or_oid = PG_GETARG_CSTRING(0);
+	Oid		   result;
 
+	if (regclass_guts(class_name_or_oid, &result, true))
 		PG_RETURN_OID(result);
-	}
-
-	/*
-	 * Normal case: parse the name into components and see if it matches any
-	 * pg_class entries in the current search path.
-	 */
-	names = stringToQualifiedNameList(class_name_or_oid);
-
-	/* We might not even have permissions on this relation; don't lock it. */
-	result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, false);
-
-	PG_RETURN_OID(result);
+	else
+		PG_RETURN_NULL();
 }
 
 /*
@@ -968,69 +806,33 @@ Datum
 regtypein(PG_FUNCTION_ARGS)
 {
 	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
-	Oid			result = InvalidOid;
-	int32		typmod;
-
-	/* '-' ? */
-	if (strcmp(typ_name_or_oid, "-") == 0)
-		PG_RETURN_OID(InvalidOid);
+	Oid			result;
 
-	/* Numeric OID? */
-	if (typ_name_or_oid[0] >= '0' &&
-		typ_name_or_oid[0] <= '9' &&
-		strspn(typ_name_or_oid, "0123456789") == strlen(typ_name_or_oid))
-	{
-		result = DatumGetObjectId(DirectFunctionCall1(oidin,
-										  CStringGetDatum(typ_name_or_oid)));
-		PG_RETURN_OID(result);
-	}
+	if (!regtype_guts(typ_name_or_oid, &result, false))
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_OBJECT),
+				 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
 
-	/* Else it's a type name, possibly schema-qualified or decorated */
-
-	/*
-	 * In bootstrap mode we assume the given name is not schema-qualified, and
-	 * just search pg_type for a match.  This is needed for initializing other
-	 * system catalogs (pg_namespace may not exist yet, and certainly there
-	 * are no schemas other than pg_catalog).
-	 */
-	if (IsBootstrapProcessingMode())
-	{
-		Relation	hdesc;
-		ScanKeyData skey[1];
-		SysScanDesc sysscan;
-		HeapTuple	tuple;
-
-		ScanKeyInit(&skey[0],
-					Anum_pg_type_typname,
-					BTEqualStrategyNumber, F_NAMEEQ,
-					CStringGetDatum(typ_name_or_oid));
-
-		hdesc = heap_open(TypeRelationId, AccessShareLock);
-		sysscan = systable_beginscan(hdesc, TypeNameNspIndexId, true,
-									 NULL, 1, skey);
-
-		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
-			result = HeapTupleGetOid(tuple);
-		else
-			ereport(ERROR,
-					(errcode(ERRCODE_UNDEFINED_OBJECT),
-					 errmsg("type \"%s\" does not exist", typ_name_or_oid)));
-
-		/* We assume there can be only one match */
+	PG_RETURN_OID(result);
+}
 
-		systable_endscan(sysscan);
-		heap_close(hdesc, AccessShareLock);
+/*
+ * to_regtype		- converts "typename" to type OID
+ *
+ * This function differs from regtypein only in returning NULL and not raising
+ * an error when the typename is not found. Note that this is not an I/O
+ * function.
+ */
+Datum
+to_regtype(PG_FUNCTION_ARGS)
+{
+	char	   *typ_name_or_oid = PG_GETARG_CSTRING(0);
+	Oid			result;
 
+	if (regtype_guts(typ_name_or_oid, &result, true))
 		PG_RETURN_OID(result);
-	}
-
-	/*
-	 * Normal case: invoke the full parser to deal with special cases such as
-	 * array syntax.
-	 */
-	parseTypeString(typ_name_or_oid, &result, &typmod);
-
-	PG_RETURN_OID(result);
+	else
+		PG_RETURN_NULL();
 }
 
 /*
@@ -1388,6 +1190,385 @@ stringToQualifiedNameList(const char *string)
  *****************************************************************************/
 
 /*
+ * Guts of regprocin and to_regproc.
+ * If the proname is found, returns true and the OID is stored into *proid_p.
+ * If not found and missing_ok is true, returns false instead of raising an
+ * error.
+ */
+static bool
+regproc_guts(char *pro_name_or_oid, RegProcedure *proid_p, bool missing_ok)
+{
+	List	   *names;
+	FuncCandidateList clist;
+
+	*proid_p = InvalidOid;
+
+	/* '-' ? */
+	if (strcmp(pro_name_or_oid, "-") == 0)
+		return true;
+
+	/* Numeric OID? */
+	if (pro_name_or_oid[0] >= '0' &&
+		pro_name_or_oid[0] <= '9' &&
+		strspn(pro_name_or_oid, "0123456789") == strlen(pro_name_or_oid))
+	{
+		*proid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
+										  CStringGetDatum(pro_name_or_oid)));
+		return true;
+	}
+
+	/* Else it's a name, possibly schema-qualified */
+
+	/*
+	 * In bootstrap mode we assume the given name is not schema-qualified, and
+	 * just search pg_proc for a unique match.	This is needed for
+	 * initializing other system catalogs (pg_namespace may not exist yet, and
+	 * certainly there are no schemas other than pg_catalog).
+	 */
+	if (IsBootstrapProcessingMode())
+	{
+		int			matches = 0;
+		Relation	hdesc;
+		ScanKeyData skey[1];
+		SysScanDesc sysscan;
+		HeapTuple	tuple;
+
+		ScanKeyInit(&skey[0],
+					Anum_pg_proc_proname,
+					BTEqualStrategyNumber, F_NAMEEQ,
+					CStringGetDatum(pro_name_or_oid));
+
+		hdesc = heap_open(ProcedureRelationId, AccessShareLock);
+		sysscan = systable_beginscan(hdesc, ProcedureNameArgsNspIndexId, true,
+									 NULL, 1, skey);
+
+		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
+		{
+			*proid_p = (RegProcedure) HeapTupleGetOid(tuple);
+			if (++matches > 1)
+				break;
+		}
+
+		systable_endscan(sysscan);
+		heap_close(hdesc, AccessShareLock);
+
+		if (matches == 0)
+		{
+			if (!missing_ok)
+				ereport(ERROR,
+						(errcode(ERRCODE_UNDEFINED_FUNCTION),
+						 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
+			return false;
+		}
+		else if (matches > 1)
+		{
+			if (!missing_ok)
+				ereport(ERROR,
+						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
+						 errmsg("more than one function named \"%s\"",
+								pro_name_or_oid)));
+			return false;
+		}
+
+		return true;
+	}
+
+	/*
+	 * Normal case: parse the name into components and see if it matches any
+	 * pg_proc entries in the current search path.
+	 */
+	names = stringToQualifiedNameList(pro_name_or_oid);
+	clist = FuncnameGetCandidates(names, -1, NIL, false, false, missing_ok);
+
+	if (clist == NULL)
+	{
+		if (!missing_ok)
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_FUNCTION),
+					 errmsg("function \"%s\" does not exist", pro_name_or_oid)));
+		return false;
+	}
+	else if (clist->next != NULL)
+	{
+		if (!missing_ok)
+			ereport(ERROR,
+					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
+					 errmsg("more than one function named \"%s\"",
+							pro_name_or_oid)));
+		return false;
+	}
+
+	*proid_p = clist->oid;
+
+	return true;
+}
+
+/*
+ * Guts of regoperin and to_regoper.
+ * If the operator is found, returns true and the OID is stored into *oprid_p.
+ * If not found and missing_ok is true, returns false instead of raising an
+ * error.
+ */
+static bool
+regoper_guts(char *opr_name_or_oid, Oid *oprid_p, bool missing_ok)
+{
+	List	   *names;
+	FuncCandidateList clist;
+
+	*oprid_p = InvalidOid;
+
+	/* '0' ? */
+	if (strcmp(opr_name_or_oid, "0") == 0)
+		return true;
+
+	/* Numeric OID? */
+	if (opr_name_or_oid[0] >= '0' &&
+		opr_name_or_oid[0] <= '9' &&
+		strspn(opr_name_or_oid, "0123456789") == strlen(opr_name_or_oid))
+	{
+		*oprid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
+										  CStringGetDatum(opr_name_or_oid)));
+		return true;
+	}
+
+	/* Else it's a name, possibly schema-qualified */
+
+	/*
+	 * In bootstrap mode we assume the given name is not schema-qualified, and
+	 * just search pg_operator for a unique match.	This is needed for
+	 * initializing other system catalogs (pg_namespace may not exist yet, and
+	 * certainly there are no schemas other than pg_catalog).
+	 */
+	if (IsBootstrapProcessingMode())
+	{
+		int			matches = 0;
+		Relation	hdesc;
+		ScanKeyData skey[1];
+		SysScanDesc sysscan;
+		HeapTuple	tuple;
+
+		ScanKeyInit(&skey[0],
+					Anum_pg_operator_oprname,
+					BTEqualStrategyNumber, F_NAMEEQ,
+					CStringGetDatum(opr_name_or_oid));
+
+		hdesc = heap_open(OperatorRelationId, AccessShareLock);
+		sysscan = systable_beginscan(hdesc, OperatorNameNspIndexId, true,
+									 NULL, 1, skey);
+
+		while (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
+		{
+			*oprid_p = HeapTupleGetOid(tuple);
+			if (++matches > 1)
+				break;
+		}
+
+		systable_endscan(sysscan);
+		heap_close(hdesc, AccessShareLock);
+
+		if (matches == 0)
+		{
+			if (!missing_ok)
+				ereport(ERROR,
+						(errcode(ERRCODE_UNDEFINED_FUNCTION),
+						 errmsg("operator does not exist: %s", opr_name_or_oid)));
+			return false;
+		}
+		else if (matches > 1)
+		{
+			if (!missing_ok)
+				ereport(ERROR,
+						(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
+						 errmsg("more than one operator named %s",
+								opr_name_or_oid)));
+			return false;
+		}
+
+		return true;
+	}
+
+	/*
+	 * Normal case: parse the name into components and see if it matches any
+	 * pg_operator entries in the current search path.
+	 */
+	names = stringToQualifiedNameList(opr_name_or_oid);
+	clist = OpernameGetCandidates(names, '\0', missing_ok);
+
+	if (clist == NULL)
+	{
+		if (!missing_ok)
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_FUNCTION),
+					 errmsg("operator does not exist: %s", opr_name_or_oid)));
+		return false;
+	}
+	else if (clist->next != NULL)
+	{
+		if (!missing_ok)
+			ereport(ERROR,
+					(errcode(ERRCODE_AMBIGUOUS_FUNCTION),
+					 errmsg("more than one operator named %s",
+							opr_name_or_oid)));
+		return false;
+	}
+
+	*oprid_p = clist->oid;
+
+	return true;
+}
+
+/*
+ * Guts of regclassin and to_regclass.
+ * If the classname is found, returns true and the OID is stored into *classid_p.
+ * If not found and missing_ok is true, or in bootstrap mode, returns false
+ * instead of raising an error
+ */
+static bool
+regclass_guts(char *class_name_or_oid, Oid *classid_p, bool missing_ok)
+{
+	List	   *names;
+	bool		result = true;
+
+	*classid_p = InvalidOid;
+
+	/* '-' ? */
+	if (strcmp(class_name_or_oid, "-") == 0)
+		return true;
+
+	/* Numeric OID? */
+	if (class_name_or_oid[0] >= '0' &&
+		class_name_or_oid[0] <= '9' &&
+		strspn(class_name_or_oid, "0123456789") == strlen(class_name_or_oid))
+	{
+		*classid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
+										  CStringGetDatum(class_name_or_oid)));
+		return true;
+	}
+
+	/* Else it's a name, possibly schema-qualified */
+
+	/*
+	 * In bootstrap mode we assume the given name is not schema-qualified, and
+	 * just search pg_class for a match.  This is needed for initializing
+	 * other system catalogs (pg_namespace may not exist yet, and certainly
+	 * there are no schemas other than pg_catalog).
+	 */
+	if (IsBootstrapProcessingMode())
+	{
+		Relation	hdesc;
+		ScanKeyData skey[1];
+		SysScanDesc sysscan;
+		HeapTuple	tuple;
+
+		ScanKeyInit(&skey[0],
+					Anum_pg_class_relname,
+					BTEqualStrategyNumber, F_NAMEEQ,
+					CStringGetDatum(class_name_or_oid));
+
+		hdesc = heap_open(RelationRelationId, AccessShareLock);
+		sysscan = systable_beginscan(hdesc, ClassNameNspIndexId, true,
+									 NULL, 1, skey);
+
+		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
+			*classid_p = HeapTupleGetOid(tuple);
+		else
+			result = false;
+
+		/* We assume there can be only one match */
+
+		systable_endscan(sysscan);
+		heap_close(hdesc, AccessShareLock);
+
+		return result;
+	}
+
+	/*
+	 * Normal case: parse the name into components and see if it matches any
+	 * pg_class entries in the current search path.
+	 */
+	names = stringToQualifiedNameList(class_name_or_oid);
+
+	/* We might not even have permissions on this relation; don't lock it. */
+	*classid_p = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, missing_ok);
+
+	return OidIsValid(*classid_p);
+}
+
+/*
+ * Guts of regtypein and to_regtype.
+ * If the type is found, returns true and the OID is stored into *typid_p.
+ * If not found and missing_ok is true, or in bootstrap mode, returns false
+ * instead of raising an error
+ */
+static bool
+regtype_guts(char *typ_name_or_oid, Oid *typid_p, bool missing_ok)
+{
+	int32		typmod;
+	bool		result = true;
+
+	*typid_p = InvalidOid;
+
+	/* '-' ? */
+	if (strcmp(typ_name_or_oid, "-") == 0)
+		return true;
+
+	/* Numeric OID? */
+	if (typ_name_or_oid[0] >= '0' &&
+		typ_name_or_oid[0] <= '9' &&
+		strspn(typ_name_or_oid, "0123456789") == strlen(typ_name_or_oid))
+	{
+		*typid_p = DatumGetObjectId(DirectFunctionCall1(oidin,
+										  CStringGetDatum(typ_name_or_oid)));
+		return true;
+	}
+
+	/* Else it's a type name, possibly schema-qualified or decorated */
+
+	/*
+	 * In bootstrap mode we assume the given name is not schema-qualified, and
+	 * just search pg_type for a match.  This is needed for initializing other
+	 * system catalogs (pg_namespace may not exist yet, and certainly there
+	 * are no schemas other than pg_catalog).
+	 */
+	if (IsBootstrapProcessingMode())
+	{
+		Relation	hdesc;
+		ScanKeyData skey[1];
+		SysScanDesc sysscan;
+		HeapTuple	tuple;
+
+		ScanKeyInit(&skey[0],
+					Anum_pg_type_typname,
+					BTEqualStrategyNumber, F_NAMEEQ,
+					CStringGetDatum(typ_name_or_oid));
+
+		hdesc = heap_open(TypeRelationId, AccessShareLock);
+		sysscan = systable_beginscan(hdesc, TypeNameNspIndexId, true,
+									 NULL, 1, skey);
+
+		if (HeapTupleIsValid(tuple = systable_getnext(sysscan)))
+			*typid_p = HeapTupleGetOid(tuple);
+		else
+			result = false;
+
+		/* We assume there can be only one match */
+
+		systable_endscan(sysscan);
+		heap_close(hdesc, AccessShareLock);
+
+		return result;
+	}
+
+	/*
+	 * Normal case: invoke the full parser to deal with special cases such as
+	 * array syntax.
+	 */
+	parseTypeString(typ_name_or_oid, typid_p, &typmod, missing_ok);
+
+	return OidIsValid(*typid_p);
+}
+
+/*
  * Given a C string, parse it into a qualified function or operator name
  * followed by a parenthesized list of type names.	Reduce the
  * type names to an array of OIDs (returned into *nargs and *argtypes;
@@ -1523,7 +1704,7 @@ parseNameAndArgTypes(const char *string, bool allowNone, List **names,
 		else
 		{
 			/* Use full parser to resolve the type name */
-			parseTypeString(typename, &typeid, &typmod);
+			parseTypeString(typename, &typeid, &typmod, false);
 		}
 		if (*nargs >= FUNC_MAX_ARGS)
 			ereport(ERROR,
diff --git a/src/include/catalog/namespace.h b/src/include/catalog/namespace.h
index b30e5e8..2f9d391 100644
--- a/src/include/catalog/namespace.h
+++ b/src/include/catalog/namespace.h
@@ -76,7 +76,8 @@ extern FuncCandidateList FuncnameGetCandidates(List *names,
 extern bool FunctionIsVisible(Oid funcid);
 
 extern Oid	OpernameGetOprid(List *names, Oid oprleft, Oid oprright);
-extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind);
+extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind,
+					  bool missing_schema_ok);
 extern bool OperatorIsVisible(Oid oprid);
 
 extern Oid	OpclassnameGetOpcid(Oid amid, const char *opcname);
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 334e6b8..21c17a0 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -173,6 +173,8 @@ DATA(insert OID =  44 (  regprocin		   PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0
 DESCR("I/O");
 DATA(insert OID =  45 (  regprocout		   PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "24" _null_ _null_ _null_ _null_ regprocout _null_ _null_ _null_ ));
 DESCR("I/O");
+DATA(insert OID = 3494 (  to_regproc		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 24 "2275" _null_ _null_ _null_ _null_ to_regproc _null_ _null_ _null_ ));
+DESCR("convert proname to regproc");
 DATA(insert OID =  46 (  textin			   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 25 "2275" _null_ _null_ _null_ _null_ textin _null_ _null_ _null_ ));
 DESCR("I/O");
 DATA(insert OID =  47 (  textout		   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2275 "25" _null_ _null_ _null_ _null_ textout _null_ _null_ _null_ ));
@@ -3304,6 +3306,8 @@ DATA(insert OID = 2214 (  regoperin			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2
 DESCR("I/O");
 DATA(insert OID = 2215 (  regoperout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2203" _null_ _null_ _null_ _null_ regoperout _null_ _null_ _null_ ));
 DESCR("I/O");
+DATA(insert OID = 3492 (  to_regoper		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2203 "2275" _null_ _null_ _null_ _null_ to_regoper _null_ _null_ _null_ ));
+DESCR("convert operator name to regoper");
 DATA(insert OID = 2216 (  regoperatorin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2204 "2275" _null_ _null_ _null_ _null_ regoperatorin _null_ _null_ _null_ ));
 DESCR("I/O");
 DATA(insert OID = 2217 (  regoperatorout	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2204" _null_ _null_ _null_ _null_ regoperatorout _null_ _null_ _null_ ));
@@ -3312,10 +3316,14 @@ DATA(insert OID = 2218 (  regclassin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2
 DESCR("I/O");
 DATA(insert OID = 2219 (  regclassout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2205" _null_ _null_ _null_ _null_ regclassout _null_ _null_ _null_ ));
 DESCR("I/O");
+DATA(insert OID = 3495 (  to_regclass		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "2275" _null_ _null_ _null_ _null_ to_regclass _null_ _null_ _null_ ));
+DESCR("convert classname to regclass");
 DATA(insert OID = 2220 (  regtypein			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ regtypein _null_ _null_ _null_ ));
 DESCR("I/O");
 DATA(insert OID = 2221 (  regtypeout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2206" _null_ _null_ _null_ _null_ regtypeout _null_ _null_ _null_ ));
 DESCR("I/O");
+DATA(insert OID = 3493 (  to_regtype		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ to_regtype _null_ _null_ _null_ ));
+DESCR("convert type name to regtype");
 DATA(insert OID = 1079 (  regclass			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "25" _null_ _null_ _null_ _null_	text_regclass _null_ _null_ _null_ ));
 DESCR("convert text to regclass");
 
diff --git a/src/include/parser/parse_type.h b/src/include/parser/parse_type.h
index ab73148..fa9cc59 100644
--- a/src/include/parser/parse_type.h
+++ b/src/include/parser/parse_type.h
@@ -47,7 +47,7 @@ extern Datum stringTypeDatum(Type tp, char *string, int32 atttypmod);
 
 extern Oid	typeidTypeRelid(Oid type_id);
 
-extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p);
+extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p, bool missing_ok);
 
 #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
 
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index 031a43a..720c831 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -597,6 +597,7 @@ extern char *regexp_fixed_prefix(text *text_re, bool case_insensitive,
 /* regproc.c */
 extern Datum regprocin(PG_FUNCTION_ARGS);
 extern Datum regprocout(PG_FUNCTION_ARGS);
+extern Datum to_regproc(PG_FUNCTION_ARGS);
 extern Datum regprocrecv(PG_FUNCTION_ARGS);
 extern Datum regprocsend(PG_FUNCTION_ARGS);
 extern Datum regprocedurein(PG_FUNCTION_ARGS);
@@ -607,6 +608,7 @@ extern Datum regoperin(PG_FUNCTION_ARGS);
 extern Datum regoperout(PG_FUNCTION_ARGS);
 extern Datum regoperrecv(PG_FUNCTION_ARGS);
 extern Datum regopersend(PG_FUNCTION_ARGS);
+extern Datum to_regoper(PG_FUNCTION_ARGS);
 extern Datum regoperatorin(PG_FUNCTION_ARGS);
 extern Datum regoperatorout(PG_FUNCTION_ARGS);
 extern Datum regoperatorrecv(PG_FUNCTION_ARGS);
@@ -615,10 +617,12 @@ extern Datum regclassin(PG_FUNCTION_ARGS);
 extern Datum regclassout(PG_FUNCTION_ARGS);
 extern Datum regclassrecv(PG_FUNCTION_ARGS);
 extern Datum regclasssend(PG_FUNCTION_ARGS);
+extern Datum to_regclass(PG_FUNCTION_ARGS);
 extern Datum regtypein(PG_FUNCTION_ARGS);
 extern Datum regtypeout(PG_FUNCTION_ARGS);
 extern Datum regtyperecv(PG_FUNCTION_ARGS);
 extern Datum regtypesend(PG_FUNCTION_ARGS);
+extern Datum to_regtype(PG_FUNCTION_ARGS);
 extern Datum regconfigin(PG_FUNCTION_ARGS);
 extern Datum regconfigout(PG_FUNCTION_ARGS);
 extern Datum regconfigrecv(PG_FUNCTION_ARGS);
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
index 7bc29a6..5fff635 100644
--- a/src/pl/plperl/plperl.c
+++ b/src/pl/plperl/plperl.c
@@ -3420,7 +3420,7 @@ plperl_spi_prepare(char *query, int argc, SV **argv)
 			char	   *typstr;
 
 			typstr = sv2cstr(argv[i]);
-			parseTypeString(typstr, &typId, &typmod);
+			parseTypeString(typstr, &typId, &typmod, false);
 			pfree(typstr);
 
 			getTypeInputInfo(typId, &typInput, &typIOParam);
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
index c0cb585..1862293 100644
--- a/src/pl/plpgsql/src/pl_gram.y
+++ b/src/pl/plpgsql/src/pl_gram.y
@@ -3462,7 +3462,7 @@ parse_datatype(const char *string, int location)
 	error_context_stack = &syntax_errcontext;
 
 	/* Let the main parser try to parse it under standard SQL rules */
-	parseTypeString(string, &type_id, &typmod);
+	parseTypeString(string, &type_id, &typmod, false);
 
 	/* Restore former ereport callback */
 	error_context_stack = syntax_errcontext.previous;
diff --git a/src/pl/plpython/plpy_spi.c b/src/pl/plpython/plpy_spi.c
index 982bf84..060d514 100644
--- a/src/pl/plpython/plpy_spi.c
+++ b/src/pl/plpython/plpy_spi.c
@@ -113,7 +113,7 @@ PLy_spi_prepare(PyObject *self, PyObject *args)
 			 *information for input conversion.
 			 ********************************************************/
 
-			parseTypeString(sptr, &typeId, &typmod);
+			parseTypeString(sptr, &typeId, &typmod, false);
 
 			typeTup = SearchSysCache1(TYPEOID,
 									  ObjectIdGetDatum(typeId));
diff --git a/src/pl/tcl/pltcl.c b/src/pl/tcl/pltcl.c
index b3bf65e..2d862a6 100644
--- a/src/pl/tcl/pltcl.c
+++ b/src/pl/tcl/pltcl.c
@@ -2165,7 +2165,7 @@ pltcl_SPI_prepare(ClientData cdata, Tcl_Interp *interp,
 						typIOParam;
 			int32		typmod;
 
-			parseTypeString(args[i], &typId, &typmod);
+			parseTypeString(args[i], &typId, &typmod, false);
 
 			getTypeInputInfo(typId, &typInput, &typIOParam);
 
diff --git a/src/test/regress/expected/regproc.out b/src/test/regress/expected/regproc.out
new file mode 100644
index 0000000..9f8d8e8
--- /dev/null
+++ b/src/test/regress/expected/regproc.out
@@ -0,0 +1,237 @@
+--
+-- regproc
+--
+/* If objects exist, return oids */
+-- without schemaname
+SELECT regoper('||/');
+ regoper 
+---------
+ ||/
+(1 row)
+
+SELECT regproc('now');
+ regproc 
+---------
+ now
+(1 row)
+
+SELECT regclass('pg_class');
+ regclass 
+----------
+ pg_class
+(1 row)
+
+SELECT regtype('int4');
+ regtype 
+---------
+ integer
+(1 row)
+
+SELECT to_regoper('||/');
+ to_regoper 
+------------
+ ||/
+(1 row)
+
+SELECT to_regproc('now');
+ to_regproc 
+------------
+ now
+(1 row)
+
+SELECT to_regclass('pg_class');
+ to_regclass 
+-------------
+ pg_class
+(1 row)
+
+SELECT to_regtype('int4');
+ to_regtype 
+------------
+ integer
+(1 row)
+
+-- with schemaname
+SELECT regoper('pg_catalog.||/');
+ regoper 
+---------
+ ||/
+(1 row)
+
+SELECT regproc('pg_catalog.now');
+ regproc 
+---------
+ now
+(1 row)
+
+SELECT regclass('pg_catalog.pg_class');
+ regclass 
+----------
+ pg_class
+(1 row)
+
+SELECT regtype('pg_catalog.int4');
+ regtype 
+---------
+ integer
+(1 row)
+
+SELECT to_regoper('pg_catalog.||/');
+ to_regoper 
+------------
+ ||/
+(1 row)
+
+SELECT to_regproc('pg_catalog.now');
+ to_regproc 
+------------
+ now
+(1 row)
+
+SELECT to_regclass('pg_catalog.pg_class');
+ to_regclass 
+-------------
+ pg_class
+(1 row)
+
+SELECT to_regtype('pg_catalog.int4');
+ to_regtype 
+------------
+ integer
+(1 row)
+
+/* If objects don't exist, raise errors. */
+-- without schemaname
+SELECT regoper('||//');
+ERROR:  operator does not exist: ||//
+LINE 3: SELECT regoper('||//');
+                       ^
+SELECT regproc('know');
+ERROR:  function "know" does not exist
+LINE 1: SELECT regproc('know');
+                       ^
+SELECT regclass('pg_classes');
+ERROR:  relation "pg_classes" does not exist
+LINE 1: SELECT regclass('pg_classes');
+                        ^
+SELECT regtype('int3');
+ERROR:  type "int3" does not exist
+LINE 1: SELECT regtype('int3');
+                       ^
+-- with schemaname
+SELECT regoper('ng_catalog.||/');
+ERROR:  schema "ng_catalog" does not exist
+LINE 1: SELECT regoper('ng_catalog.||/');
+                       ^
+SELECT regproc('ng_catalog.now');
+ERROR:  schema "ng_catalog" does not exist
+LINE 1: SELECT regproc('ng_catalog.now');
+                       ^
+SELECT regclass('ng_catalog.pg_class');
+ERROR:  schema "ng_catalog" does not exist
+LINE 1: SELECT regclass('ng_catalog.pg_class');
+                        ^
+SELECT regtype('ng_catalog.int4');
+ERROR:  schema "ng_catalog" does not exist
+LINE 1: SELECT regtype('ng_catalog.int4');
+                       ^
+/* If objects don't exist, return NULL with no error. */
+-- without schemaname
+SELECT to_regoper('||//');
+ to_regoper 
+------------
+ 
+(1 row)
+
+SELECT to_regproc('know');
+ to_regproc 
+------------
+ 
+(1 row)
+
+SELECT to_regclass('pg_classes');
+ to_regclass 
+-------------
+ 
+(1 row)
+
+SELECT to_regtype('int3');
+ to_regtype 
+------------
+ 
+(1 row)
+
+-- with schemaname
+SELECT to_regoper('ng_catalog.||/');
+ to_regoper 
+------------
+ 
+(1 row)
+
+SELECT to_regproc('ng_catalog.now');
+ to_regproc 
+------------
+ 
+(1 row)
+
+SELECT to_regclass('ng_catalog.pg_class');
+ to_regclass 
+-------------
+ 
+(1 row)
+
+SELECT to_regtype('ng_catalog.int4');
+ to_regtype 
+------------
+ 
+(1 row)
+
+/* Cast 0 to InvalidOid */
+SELECT regoper('0');
+ regoper 
+---------
+ 0
+(1 row)
+
+SELECT regproc('0');
+ regproc 
+---------
+ -
+(1 row)
+
+SELECT regclass('0');
+ regclass 
+----------
+ -
+(1 row)
+
+SELECT regtype('0');
+ regtype 
+---------
+ -
+(1 row)
+
+SELECT to_regoper('0');
+ to_regoper 
+------------
+ 0
+(1 row)
+
+SELECT to_regproc('0');
+ to_regproc 
+------------
+ -
+(1 row)
+
+SELECT to_regclass('0');
+ to_regclass 
+-------------
+ -
+(1 row)
+
+SELECT to_regtype('0');
+ to_regtype 
+------------
+ -
+(1 row)
+
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index c62be2a..c0416f4 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -13,7 +13,7 @@ test: tablespace
 # ----------
 # The first group of parallel tests
 # ----------
-test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes pg_lsn
+test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes pg_lsn regproc
 
 # Depends on things setup during char, varchar and text
 test: strings
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
index 885ca9a..16a1905 100644
--- a/src/test/regress/serial_schedule
+++ b/src/test/regress/serial_schedule
@@ -20,6 +20,7 @@ test: enum
 test: money
 test: rangetypes
 test: pg_lsn
+test: regproc
 test: strings
 test: numerology
 test: point
diff --git a/src/test/regress/sql/regproc.sql b/src/test/regress/sql/regproc.sql
new file mode 100644
index 0000000..3cfa726
--- /dev/null
+++ b/src/test/regress/sql/regproc.sql
@@ -0,0 +1,74 @@
+--
+-- regproc
+--
+
+/* If objects exist, return oids */
+
+-- without schemaname
+
+SELECT regoper('||/');
+SELECT regproc('now');
+SELECT regclass('pg_class');
+SELECT regtype('int4');
+
+SELECT to_regoper('||/');
+SELECT to_regproc('now');
+SELECT to_regclass('pg_class');
+SELECT to_regtype('int4');
+
+-- with schemaname
+
+SELECT regoper('pg_catalog.||/');
+SELECT regproc('pg_catalog.now');
+SELECT regclass('pg_catalog.pg_class');
+SELECT regtype('pg_catalog.int4');
+
+SELECT to_regoper('pg_catalog.||/');
+SELECT to_regproc('pg_catalog.now');
+SELECT to_regclass('pg_catalog.pg_class');
+SELECT to_regtype('pg_catalog.int4');
+
+/* If objects don't exist, raise errors. */
+
+-- without schemaname
+
+SELECT regoper('||//');
+SELECT regproc('know');
+SELECT regclass('pg_classes');
+SELECT regtype('int3');
+
+-- with schemaname
+
+SELECT regoper('ng_catalog.||/');
+SELECT regproc('ng_catalog.now');
+SELECT regclass('ng_catalog.pg_class');
+SELECT regtype('ng_catalog.int4');
+
+/* If objects don't exist, return NULL with no error. */
+
+-- without schemaname
+
+SELECT to_regoper('||//');
+SELECT to_regproc('know');
+SELECT to_regclass('pg_classes');
+SELECT to_regtype('int3');
+
+-- with schemaname
+
+SELECT to_regoper('ng_catalog.||/');
+SELECT to_regproc('ng_catalog.now');
+SELECT to_regclass('ng_catalog.pg_class');
+SELECT to_regtype('ng_catalog.int4');
+
+/* Cast 0 to InvalidOid */
+
+SELECT regoper('0');
+SELECT regproc('0');
+SELECT regclass('0');
+SELECT regtype('0');
+
+SELECT to_regoper('0');
+SELECT to_regproc('0');
+SELECT to_regclass('0');
+SELECT to_regtype('0');
+

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
new file mode 100644
index 6e2fbda..bd97460
*** a/doc/src/sgml/func.sgml
--- b/doc/src/sgml/func.sgml
*************** SELECT pg_type_is_visible('myschema.widg
*** 15279,15284 ****
--- 15279,15300 ----
      <primary>collation for</primary>
     </indexterm>
  
+    <indexterm>
+     <primary>to_regclass</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regproc</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regoper</primary>
+    </indexterm>
+ 
+    <indexterm>
+     <primary>to_regtype</primary>
+    </indexterm>
+ 
    <para>
     <xref linkend="functions-info-catalog-table"> lists functions that
     extract information from the system catalogs.
*************** SELECT pg_type_is_visible('myschema.widg
*** 15449,15454 ****
--- 15465,15490 ----
         <entry><type>text</type></entry>
         <entry>get the collation of the argument</entry>
        </row>
+       <row>
+        <entry><literal><function>to_regclass(<parameter>rel_name</parameter>)</function></literal></entry>
+        <entry><type>regclass</type></entry>
+        <entry>get the oid of the named relation</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regproc(<parameter>func_name</parameter>)</function></literal></entry>
+        <entry><type>regproc</type></entry>
+        <entry>get the oid of the named function</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regoper(<parameter>operator_name</parameter>)</function></literal></entry>
+        <entry><type>regoper</type></entry>
+        <entry>get the oid of the named operator</entry>
+       </row>
+       <row>
+        <entry><literal><function>to_regtype(<parameter>type_name</parameter>)</function></literal></entry>
+        <entry><type>regtype</type></entry>
+        <entry>get the oid of the named type</entry>
+       </row>
       </tbody>
      </tgroup>
     </table>
*************** SELECT collation for ('foo' COLLATE "de_
*** 15614,15619 ****
--- 15650,15667 ----
    is not of a collatable data type, then an error is raised.
    </para>
  
+   <para>
+    The <function>to_regclass</function>, <function>to_regproc</function>,
+    <function>to_regoper</function> and <function>to_regtype</function>
+    work like casts to <type>regclass</>, <type>regproc</>, <type>regoper</> and
+    <type>regtype</>, respectively, except that they return NULL when no
+    object by that name is found, or in the case of
+    <function>to_regproc</function> and <function>to_regoper</function>
+    when more than one object with that name is found, rather than raising
+    an error. In addition, these don't accept a numeric OID; the input must be
+    an existing object name.
+   </para>
+ 
     <indexterm>
      <primary>col_description</primary>
     </indexterm>
diff --git a/src/backend/catalog/namespace.c b/src/backend/catalog/namespace.c
new file mode 100644
index 6c2a5d2..5bf6d28
*** a/src/backend/catalog/namespace.c
--- b/src/backend/catalog/namespace.c
*************** OpernameGetOprid(List *names, Oid oprlef
*** 1556,1562 ****
   * will be InvalidOid for a prefix or postfix oprkind.	nargs is 2, too.
   */
  FuncCandidateList
! OpernameGetCandidates(List *names, char oprkind)
  {
  	FuncCandidateList resultList = NULL;
  	char	   *resultSpace = NULL;
--- 1556,1562 ----
   * will be InvalidOid for a prefix or postfix oprkind.	nargs is 2, too.
   */
  FuncCandidateList
! OpernameGetCandidates(List *names, char oprkind, bool missing_schema_ok)
  {
  	FuncCandidateList resultList = NULL;
  	char	   *resultSpace = NULL;
*************** OpernameGetCandidates(List *names, char 
*** 1573,1579 ****
  	if (schemaname)
  	{
  		/* use exact schema given */
! 		namespaceId = LookupExplicitNamespace(schemaname, false);
  	}
  	else
  	{
--- 1573,1581 ----
  	if (schemaname)
  	{
  		/* use exact schema given */
! 		namespaceId = LookupExplicitNamespace(schemaname, missing_schema_ok);
! 		if (missing_schema_ok && !OidIsValid(namespaceId))
! 			return NULL;
  	}
  	else
  	{
diff --git a/src/backend/parser/parse_oper.c b/src/backend/parser/parse_oper.c
new file mode 100644
index 99dbd30..a2b712d
*** a/src/backend/parser/parse_oper.c
--- b/src/backend/parser/parse_oper.c
*************** oper(ParseState *pstate, List *opname, O
*** 407,413 ****
  		FuncCandidateList clist;
  
  		/* Get binary operators of given name */
! 		clist = OpernameGetCandidates(opname, 'b');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 407,413 ----
  		FuncCandidateList clist;
  
  		/* Get binary operators of given name */
! 		clist = OpernameGetCandidates(opname, 'b', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
*************** right_oper(ParseState *pstate, List *op,
*** 553,559 ****
  		FuncCandidateList clist;
  
  		/* Get postfix operators of given name */
! 		clist = OpernameGetCandidates(op, 'r');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 553,559 ----
  		FuncCandidateList clist;
  
  		/* Get postfix operators of given name */
! 		clist = OpernameGetCandidates(op, 'r', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
*************** left_oper(ParseState *pstate, List *op, 
*** 631,637 ****
  		FuncCandidateList clist;
  
  		/* Get prefix operators of given name */
! 		clist = OpernameGetCandidates(op, 'l');
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
--- 631,637 ----
  		FuncCandidateList clist;
  
  		/* Get prefix operators of given name */
! 		clist = OpernameGetCandidates(op, 'l', false);
  
  		/* No operators found? Then fail... */
  		if (clist != NULL)
diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
new file mode 100644
index b329dfb..b8c10e1
*** a/src/backend/parser/parse_type.c
--- b/src/backend/parser/parse_type.c
*************** pts_error_callback(void *arg)
*** 706,714 ****
   * Given a string that is supposed to be a SQL-compatible type declaration,
   * such as "int4" or "integer" or "character varying(32)", parse
   * the string and convert it to a type OID and type modifier.
   */
  void
! parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p)
  {
  	StringInfoData buf;
  	List	   *raw_parsetree_list;
--- 706,717 ----
   * Given a string that is supposed to be a SQL-compatible type declaration,
   * such as "int4" or "integer" or "character varying(32)", parse
   * the string and convert it to a type OID and type modifier.
+  * If missing_ok is true, InvalidOid is returned rather than raising an error
+  * when the type name is not found.
   */
  void
! parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p,
! 				bool missing_ok)
  {
  	StringInfoData buf;
  	List	   *raw_parsetree_list;
*************** parseTypeString(const char *str, Oid *ty
*** 717,722 ****
--- 720,726 ----
  	TypeCast   *typecast;
  	TypeName   *typeName;
  	ErrorContextCallback ptserrcontext;
+ 	Type		tup;
  
  	/* make sure we give useful error for empty input */
  	if (strspn(str, " \t\n\r\f") == strlen(str))
*************** parseTypeString(const char *str, Oid *ty
*** 782,788 ****
  	if (typeName->setof)
  		goto fail;
  
! 	typenameTypeIdAndMod(NULL, typeName, typeid_p, typmod_p);
  
  	pfree(buf.data);
  
--- 786,813 ----
  	if (typeName->setof)
  		goto fail;
  
! 	tup = LookupTypeName(NULL, typeName, typmod_p, missing_ok);
! 	if (tup == NULL)
! 	{
! 		if (!missing_ok)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_OBJECT),
! 					errmsg("type \"%s\" does not exist",
! 							TypeNameToString(typeName)),
! 					parser_errposition(NULL, typeName->location)));
! 		*typeid_p = InvalidOid;
! 	}
! 	else
! 	{
! 		if (!((Form_pg_type) GETSTRUCT(tup))->typisdefined)
! 			ereport(ERROR,
! 					(errcode(ERRCODE_UNDEFINED_OBJECT),
! 					errmsg("type \"%s\" is only a shell",
! 							TypeNameToString(typeName)),
! 					parser_errposition(NULL, typeName->location)));
! 		*typeid_p = HeapTupleGetOid(tup);
! 		ReleaseSysCache(tup);
! 	}
  
  	pfree(buf.data);
  
diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
new file mode 100644
index 5d73562..eeb8ee8
*** a/src/backend/utils/adt/regproc.c
--- b/src/backend/utils/adt/regproc.c
*************** regprocin(PG_FUNCTION_ARGS)
*** 153,158 ****
--- 153,189 ----
  }
  
  /*
+  * to_regproc	- converts "proname" to proc OID
+  *
+  * This function differs from regprocin only in returning NULL and not raising
+  * an error when the proname is not found or more than one proname is found.
+  * In addition, this doesn't accept a numeric OID or '-' that signifies unknown
+  * (OID 0). Note that this is not an I/O function.
+  *
+  * This function is not needed in bootstrap mode, so we don't worry about
+  * making it work then.
+  */
+ Datum
+ to_regproc(PG_FUNCTION_ARGS)
+ {
+ 	char	   *pro_name = PG_GETARG_CSTRING(0);
+ 	List	   *names;
+ 	FuncCandidateList clist;
+ 
+ 	/*
+ 	 * Parse the name into components and see if it matches any pg_proc entries
+ 	 * in the current search path.
+ 	 */
+ 	names = stringToQualifiedNameList(pro_name);
+ 	clist = FuncnameGetCandidates(names, -1, NIL, false, false, true);
+ 
+ 	if (clist == NULL || clist->next != NULL)
+ 		PG_RETURN_NULL();
+ 
+ 	PG_RETURN_OID(clist->oid);
+ }
+ 
+ /*
   * regprocout		- converts proc OID to "pro_name"
   */
  Datum
*************** regoperin(PG_FUNCTION_ARGS)
*** 502,508 ****
  	 * pg_operator entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(opr_name_or_oid);
! 	clist = OpernameGetCandidates(names, '\0');
  
  	if (clist == NULL)
  		ereport(ERROR,
--- 533,539 ----
  	 * pg_operator entries in the current search path.
  	 */
  	names = stringToQualifiedNameList(opr_name_or_oid);
! 	clist = OpernameGetCandidates(names, '\0', false);
  
  	if (clist == NULL)
  		ereport(ERROR,
*************** regoperin(PG_FUNCTION_ARGS)
*** 520,525 ****
--- 551,587 ----
  }
  
  /*
+  * to_regoper		- converts "oprname" to operator OID
+  *
+  * This function differs from regoperin only in returning NULL and not raising
+  * an error when the opername is not found or more than one opername is found.
+  * In addition, this doesn't accept a numeric OID. Note that this is not an I/O
+  * function.
+  *
+  * This function is not needed in bootstrap mode, so we don't worry about
+  * making it work then.
+  */
+ Datum
+ to_regoper(PG_FUNCTION_ARGS)
+ {
+ 	char	   *opr_name = PG_GETARG_CSTRING(0);
+ 	List	   *names;
+ 	FuncCandidateList clist;
+ 
+ 	/*
+ 	 * Parse the name into components and see if it matches any pg_operator
+ 	 * entries in the current search path.
+ 	 */
+ 	names = stringToQualifiedNameList(opr_name);
+ 	clist = OpernameGetCandidates(names, '\0', true);
+ 
+ 	if (clist == NULL || clist->next != NULL)
+ 		PG_RETURN_NULL();
+ 
+ 	PG_RETURN_OID(clist->oid);
+ }
+ 
+ /*
   * regoperout		- converts operator OID to "opr_name"
   */
  Datum
*************** regoperout(PG_FUNCTION_ARGS)
*** 558,564 ****
  			 * qualify it.
  			 */
  			clist = OpernameGetCandidates(list_make1(makeString(oprname)),
! 										  '\0');
  			if (clist != NULL && clist->next == NULL &&
  				clist->oid == oprid)
  				result = pstrdup(oprname);
--- 620,626 ----
  			 * qualify it.
  			 */
  			clist = OpernameGetCandidates(list_make1(makeString(oprname)),
! 										  '\0', false);
  			if (clist != NULL && clist->next == NULL &&
  				clist->oid == oprid)
  				result = pstrdup(oprname);
*************** regclassin(PG_FUNCTION_ARGS)
*** 873,878 ****
--- 935,973 ----
  }
  
  /*
+  * to_regclass		- converts "classname" to class OID
+  *
+  * This function differs from regclassin only in returning NULL and not raising
+  * an error when the classname is not found. In addition, this doesn't accept a
+  * numeric OID or '-' that signifies unknown (OID 0). Note that this is not an
+  * I/O function.
+  *
+  * This function is not needed in bootstrap mode, so we don't worry about
+  * making it work then.
+  */
+ Datum
+ to_regclass(PG_FUNCTION_ARGS)
+ {
+ 	char	   *class_name = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 	List	   *names;
+ 
+ 	/*
+ 	 * Parse the name into components and see if it matches any pg_class entries
+ 	 * in the current search path.
+ 	 */
+ 	names = stringToQualifiedNameList(class_name);
+ 
+ 	/* We might not even have permissions on this relation; don't lock it. */
+ 	result = RangeVarGetRelid(makeRangeVarFromNameList(names), NoLock, true);
+ 
+ 	if (OidIsValid(result))
+ 		PG_RETURN_OID(result);
+ 	else
+ 		PG_RETURN_NULL();
+ }
+ 
+ /*
   * regclassout		- converts class OID to "class_name"
   */
  Datum
*************** regtypein(PG_FUNCTION_ARGS)
*** 1028,1039 ****
  	 * Normal case: invoke the full parser to deal with special cases such as
  	 * array syntax.
  	 */
! 	parseTypeString(typ_name_or_oid, &result, &typmod);
  
  	PG_RETURN_OID(result);
  }
  
  /*
   * regtypeout		- converts type OID to "typ_name"
   */
  Datum
--- 1123,1163 ----
  	 * Normal case: invoke the full parser to deal with special cases such as
  	 * array syntax.
  	 */
! 	parseTypeString(typ_name_or_oid, &result, &typmod, false);
  
  	PG_RETURN_OID(result);
  }
  
  /*
+  * to_regtype		- converts "typename" to type OID
+  *
+  * This function differs from regtypein only in returning NULL and not raising
+  * an error when the typename is not found. Note that this is not an I/O
+  * function. In addition, this doesn't accept a numeric OID or '-' that
+  * signifies unknown (OID 0). Note that this is not an I/O function.
+  *
+  * This function is not needed in bootstrap mode, so we don't worry about
+  * making it work then.
+  */
+ Datum
+ to_regtype(PG_FUNCTION_ARGS)
+ {
+ 	char	   *typ_name = PG_GETARG_CSTRING(0);
+ 	Oid			result;
+ 	int32		typmod;
+ 
+ 	/*
+ 	 * Invoke the full parser to deal with special cases such as array syntax.
+ 	 */
+ 	parseTypeString(typ_name, &result, &typmod, true);
+ 
+ 	if (OidIsValid(result))
+ 		PG_RETURN_OID(result);
+ 	else
+ 		PG_RETURN_NULL();
+ }
+ 
+ /*
   * regtypeout		- converts type OID to "typ_name"
   */
  Datum
*************** parseNameAndArgTypes(const char *string,
*** 1523,1529 ****
  		else
  		{
  			/* Use full parser to resolve the type name */
! 			parseTypeString(typename, &typeid, &typmod);
  		}
  		if (*nargs >= FUNC_MAX_ARGS)
  			ereport(ERROR,
--- 1647,1653 ----
  		else
  		{
  			/* Use full parser to resolve the type name */
! 			parseTypeString(typename, &typeid, &typmod, false);
  		}
  		if (*nargs >= FUNC_MAX_ARGS)
  			ereport(ERROR,
diff --git a/src/include/catalog/namespace.h b/src/include/catalog/namespace.h
new file mode 100644
index b30e5e8..2f9d391
*** a/src/include/catalog/namespace.h
--- b/src/include/catalog/namespace.h
*************** extern FuncCandidateList FuncnameGetCand
*** 76,82 ****
  extern bool FunctionIsVisible(Oid funcid);
  
  extern Oid	OpernameGetOprid(List *names, Oid oprleft, Oid oprright);
! extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind);
  extern bool OperatorIsVisible(Oid oprid);
  
  extern Oid	OpclassnameGetOpcid(Oid amid, const char *opcname);
--- 76,83 ----
  extern bool FunctionIsVisible(Oid funcid);
  
  extern Oid	OpernameGetOprid(List *names, Oid oprleft, Oid oprright);
! extern FuncCandidateList OpernameGetCandidates(List *names, char oprkind,
! 					  bool missing_schema_ok);
  extern bool OperatorIsVisible(Oid oprid);
  
  extern Oid	OpclassnameGetOpcid(Oid amid, const char *opcname);
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
new file mode 100644
index 334e6b8..21c17a0
*** a/src/include/catalog/pg_proc.h
--- b/src/include/catalog/pg_proc.h
*************** DATA(insert OID =  44 (  regprocin		   P
*** 173,178 ****
--- 173,180 ----
  DESCR("I/O");
  DATA(insert OID =  45 (  regprocout		   PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "24" _null_ _null_ _null_ _null_ regprocout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3494 (  to_regproc		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 24 "2275" _null_ _null_ _null_ _null_ to_regproc _null_ _null_ _null_ ));
+ DESCR("convert proname to regproc");
  DATA(insert OID =  46 (  textin			   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 25 "2275" _null_ _null_ _null_ _null_ textin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID =  47 (  textout		   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2275 "25" _null_ _null_ _null_ _null_ textout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2214 (  regoperin			PG
*** 3304,3309 ****
--- 3306,3313 ----
  DESCR("I/O");
  DATA(insert OID = 2215 (  regoperout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2203" _null_ _null_ _null_ _null_ regoperout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3492 (  to_regoper		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2203 "2275" _null_ _null_ _null_ _null_ to_regoper _null_ _null_ _null_ ));
+ DESCR("convert operator name to regoper");
  DATA(insert OID = 2216 (  regoperatorin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2204 "2275" _null_ _null_ _null_ _null_ regoperatorin _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2217 (  regoperatorout	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2204" _null_ _null_ _null_ _null_ regoperatorout _null_ _null_ _null_ ));
*************** DATA(insert OID = 2218 (  regclassin		PG
*** 3312,3321 ****
--- 3316,3329 ----
  DESCR("I/O");
  DATA(insert OID = 2219 (  regclassout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2205" _null_ _null_ _null_ _null_ regclassout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3495 (  to_regclass		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "2275" _null_ _null_ _null_ _null_ to_regclass _null_ _null_ _null_ ));
+ DESCR("convert classname to regclass");
  DATA(insert OID = 2220 (  regtypein			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ regtypein _null_ _null_ _null_ ));
  DESCR("I/O");
  DATA(insert OID = 2221 (  regtypeout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2206" _null_ _null_ _null_ _null_ regtypeout _null_ _null_ _null_ ));
  DESCR("I/O");
+ DATA(insert OID = 3493 (  to_regtype		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2206 "2275" _null_ _null_ _null_ _null_ to_regtype _null_ _null_ _null_ ));
+ DESCR("convert type name to regtype");
  DATA(insert OID = 1079 (  regclass			PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2205 "25" _null_ _null_ _null_ _null_	text_regclass _null_ _null_ _null_ ));
  DESCR("convert text to regclass");
  
diff --git a/src/include/parser/parse_type.h b/src/include/parser/parse_type.h
new file mode 100644
index ab73148..fa9cc59
*** a/src/include/parser/parse_type.h
--- b/src/include/parser/parse_type.h
*************** extern Datum stringTypeDatum(Type tp, ch
*** 47,53 ****
  
  extern Oid	typeidTypeRelid(Oid type_id);
  
! extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p);
  
  #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
  
--- 47,53 ----
  
  extern Oid	typeidTypeRelid(Oid type_id);
  
! extern void parseTypeString(const char *str, Oid *typeid_p, int32 *typmod_p, bool missing_ok);
  
  #define ISCOMPLEX(typeid) (typeidTypeRelid(typeid) != InvalidOid)
  
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
new file mode 100644
index 031a43a..720c831
*** a/src/include/utils/builtins.h
--- b/src/include/utils/builtins.h
*************** extern char *regexp_fixed_prefix(text *t
*** 597,602 ****
--- 597,603 ----
  /* regproc.c */
  extern Datum regprocin(PG_FUNCTION_ARGS);
  extern Datum regprocout(PG_FUNCTION_ARGS);
+ extern Datum to_regproc(PG_FUNCTION_ARGS);
  extern Datum regprocrecv(PG_FUNCTION_ARGS);
  extern Datum regprocsend(PG_FUNCTION_ARGS);
  extern Datum regprocedurein(PG_FUNCTION_ARGS);
*************** extern Datum regoperin(PG_FUNCTION_ARGS)
*** 607,612 ****
--- 608,614 ----
  extern Datum regoperout(PG_FUNCTION_ARGS);
  extern Datum regoperrecv(PG_FUNCTION_ARGS);
  extern Datum regopersend(PG_FUNCTION_ARGS);
+ extern Datum to_regoper(PG_FUNCTION_ARGS);
  extern Datum regoperatorin(PG_FUNCTION_ARGS);
  extern Datum regoperatorout(PG_FUNCTION_ARGS);
  extern Datum regoperatorrecv(PG_FUNCTION_ARGS);
*************** extern Datum regclassin(PG_FUNCTION_ARGS
*** 615,624 ****
--- 617,628 ----
  extern Datum regclassout(PG_FUNCTION_ARGS);
  extern Datum regclassrecv(PG_FUNCTION_ARGS);
  extern Datum regclasssend(PG_FUNCTION_ARGS);
+ extern Datum to_regclass(PG_FUNCTION_ARGS);
  extern Datum regtypein(PG_FUNCTION_ARGS);
  extern Datum regtypeout(PG_FUNCTION_ARGS);
  extern Datum regtyperecv(PG_FUNCTION_ARGS);
  extern Datum regtypesend(PG_FUNCTION_ARGS);
+ extern Datum to_regtype(PG_FUNCTION_ARGS);
  extern Datum regconfigin(PG_FUNCTION_ARGS);
  extern Datum regconfigout(PG_FUNCTION_ARGS);
  extern Datum regconfigrecv(PG_FUNCTION_ARGS);
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
new file mode 100644
index 7bc29a6..5fff635
*** a/src/pl/plperl/plperl.c
--- b/src/pl/plperl/plperl.c
*************** plperl_spi_prepare(char *query, int argc
*** 3420,3426 ****
  			char	   *typstr;
  
  			typstr = sv2cstr(argv[i]);
! 			parseTypeString(typstr, &typId, &typmod);
  			pfree(typstr);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
--- 3420,3426 ----
  			char	   *typstr;
  
  			typstr = sv2cstr(argv[i]);
! 			parseTypeString(typstr, &typId, &typmod, false);
  			pfree(typstr);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
diff --git a/src/pl/plpgsql/src/pl_gram.y b/src/pl/plpgsql/src/pl_gram.y
new file mode 100644
index 91186c6..e3a992c
*** a/src/pl/plpgsql/src/pl_gram.y
--- b/src/pl/plpgsql/src/pl_gram.y
*************** parse_datatype(const char *string, int l
*** 3492,3498 ****
  	error_context_stack = &syntax_errcontext;
  
  	/* Let the main parser try to parse it under standard SQL rules */
! 	parseTypeString(string, &type_id, &typmod);
  
  	/* Restore former ereport callback */
  	error_context_stack = syntax_errcontext.previous;
--- 3492,3498 ----
  	error_context_stack = &syntax_errcontext;
  
  	/* Let the main parser try to parse it under standard SQL rules */
! 	parseTypeString(string, &type_id, &typmod, false);
  
  	/* Restore former ereport callback */
  	error_context_stack = syntax_errcontext.previous;
diff --git a/src/pl/plpython/plpy_spi.c b/src/pl/plpython/plpy_spi.c
new file mode 100644
index 982bf84..060d514
*** a/src/pl/plpython/plpy_spi.c
--- b/src/pl/plpython/plpy_spi.c
*************** PLy_spi_prepare(PyObject *self, PyObject
*** 113,119 ****
  			 *information for input conversion.
  			 ********************************************************/
  
! 			parseTypeString(sptr, &typeId, &typmod);
  
  			typeTup = SearchSysCache1(TYPEOID,
  									  ObjectIdGetDatum(typeId));
--- 113,119 ----
  			 *information for input conversion.
  			 ********************************************************/
  
! 			parseTypeString(sptr, &typeId, &typmod, false);
  
  			typeTup = SearchSysCache1(TYPEOID,
  									  ObjectIdGetDatum(typeId));
diff --git a/src/pl/tcl/pltcl.c b/src/pl/tcl/pltcl.c
new file mode 100644
index b3bf65e..2d862a6
*** a/src/pl/tcl/pltcl.c
--- b/src/pl/tcl/pltcl.c
*************** pltcl_SPI_prepare(ClientData cdata, Tcl_
*** 2165,2171 ****
  						typIOParam;
  			int32		typmod;
  
! 			parseTypeString(args[i], &typId, &typmod);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
  
--- 2165,2171 ----
  						typIOParam;
  			int32		typmod;
  
! 			parseTypeString(args[i], &typId, &typmod, false);
  
  			getTypeInputInfo(typId, &typInput, &typIOParam);
  
diff --git a/src/test/regress/expected/regproc.out b/src/test/regress/expected/regproc.out
new file mode 100644
index ...56ab245
*** a/src/test/regress/expected/regproc.out
--- b/src/test/regress/expected/regproc.out
***************
*** 0 ****
--- 1,188 ----
+ --
+ -- regproc
+ --
+ /* If objects exist, return oids */
+ -- without schemaname
+ SELECT regoper('||/');
+  regoper 
+ ---------
+  ||/
+ (1 row)
+ 
+ SELECT regproc('now');
+  regproc 
+ ---------
+  now
+ (1 row)
+ 
+ SELECT regclass('pg_class');
+  regclass 
+ ----------
+  pg_class
+ (1 row)
+ 
+ SELECT regtype('int4');
+  regtype 
+ ---------
+  integer
+ (1 row)
+ 
+ SELECT to_regoper('||/');
+  to_regoper 
+ ------------
+  ||/
+ (1 row)
+ 
+ SELECT to_regproc('now');
+  to_regproc 
+ ------------
+  now
+ (1 row)
+ 
+ SELECT to_regclass('pg_class');
+  to_regclass 
+ -------------
+  pg_class
+ (1 row)
+ 
+ SELECT to_regtype('int4');
+  to_regtype 
+ ------------
+  integer
+ (1 row)
+ 
+ -- with schemaname
+ SELECT regoper('pg_catalog.||/');
+  regoper 
+ ---------
+  ||/
+ (1 row)
+ 
+ SELECT regproc('pg_catalog.now');
+  regproc 
+ ---------
+  now
+ (1 row)
+ 
+ SELECT regclass('pg_catalog.pg_class');
+  regclass 
+ ----------
+  pg_class
+ (1 row)
+ 
+ SELECT regtype('pg_catalog.int4');
+  regtype 
+ ---------
+  integer
+ (1 row)
+ 
+ SELECT to_regoper('pg_catalog.||/');
+  to_regoper 
+ ------------
+  ||/
+ (1 row)
+ 
+ SELECT to_regproc('pg_catalog.now');
+  to_regproc 
+ ------------
+  now
+ (1 row)
+ 
+ SELECT to_regclass('pg_catalog.pg_class');
+  to_regclass 
+ -------------
+  pg_class
+ (1 row)
+ 
+ SELECT to_regtype('pg_catalog.int4');
+  to_regtype 
+ ------------
+  integer
+ (1 row)
+ 
+ /* If objects don't exist, raise errors. */
+ -- without schemaname
+ SELECT regoper('||//');
+ ERROR:  operator does not exist: ||//
+ LINE 3: SELECT regoper('||//');
+                        ^
+ SELECT regproc('know');
+ ERROR:  function "know" does not exist
+ LINE 1: SELECT regproc('know');
+                        ^
+ SELECT regclass('pg_classes');
+ ERROR:  relation "pg_classes" does not exist
+ LINE 1: SELECT regclass('pg_classes');
+                         ^
+ SELECT regtype('int3');
+ ERROR:  type "int3" does not exist
+ LINE 1: SELECT regtype('int3');
+                        ^
+ -- with schemaname
+ SELECT regoper('ng_catalog.||/');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regoper('ng_catalog.||/');
+                        ^
+ SELECT regproc('ng_catalog.now');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regproc('ng_catalog.now');
+                        ^
+ SELECT regclass('ng_catalog.pg_class');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regclass('ng_catalog.pg_class');
+                         ^
+ SELECT regtype('ng_catalog.int4');
+ ERROR:  schema "ng_catalog" does not exist
+ LINE 1: SELECT regtype('ng_catalog.int4');
+                        ^
+ /* If objects don't exist, return NULL with no error. */
+ -- without schemaname
+ SELECT to_regoper('||//');
+  to_regoper 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regproc('know');
+  to_regproc 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regclass('pg_classes');
+  to_regclass 
+ -------------
+  
+ (1 row)
+ 
+ SELECT to_regtype('int3');
+  to_regtype 
+ ------------
+  
+ (1 row)
+ 
+ -- with schemaname
+ SELECT to_regoper('ng_catalog.||/');
+  to_regoper 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regproc('ng_catalog.now');
+  to_regproc 
+ ------------
+  
+ (1 row)
+ 
+ SELECT to_regclass('ng_catalog.pg_class');
+  to_regclass 
+ -------------
+  
+ (1 row)
+ 
+ SELECT to_regtype('ng_catalog.int4');
+  to_regtype 
+ ------------
+  
+ (1 row)
+ 
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
new file mode 100644
index c62be2a..c0416f4
*** a/src/test/regress/parallel_schedule
--- b/src/test/regress/parallel_schedule
*************** test: tablespace
*** 13,19 ****
  # ----------
  # The first group of parallel tests
  # ----------
! test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes pg_lsn
  
  # Depends on things setup during char, varchar and text
  test: strings
--- 13,19 ----
  # ----------
  # The first group of parallel tests
  # ----------
! test: boolean char name varchar text int2 int4 int8 oid float4 float8 bit numeric txid uuid enum money rangetypes pg_lsn regproc
  
  # Depends on things setup during char, varchar and text
  test: strings
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
new file mode 100644
index 885ca9a..16a1905
*** a/src/test/regress/serial_schedule
--- b/src/test/regress/serial_schedule
*************** test: enum
*** 20,25 ****
--- 20,26 ----
  test: money
  test: rangetypes
  test: pg_lsn
+ test: regproc
  test: strings
  test: numerology
  test: point
diff --git a/src/test/regress/sql/regproc.sql b/src/test/regress/sql/regproc.sql
new file mode 100644
index ...1334cfb
*** a/src/test/regress/sql/regproc.sql
--- b/src/test/regress/sql/regproc.sql
***************
*** 0 ****
--- 1,61 ----
+ --
+ -- regproc
+ --
+ 
+ /* If objects exist, return oids */
+ 
+ -- without schemaname
+ 
+ SELECT regoper('||/');
+ SELECT regproc('now');
+ SELECT regclass('pg_class');
+ SELECT regtype('int4');
+ 
+ SELECT to_regoper('||/');
+ SELECT to_regproc('now');
+ SELECT to_regclass('pg_class');
+ SELECT to_regtype('int4');
+ 
+ -- with schemaname
+ 
+ SELECT regoper('pg_catalog.||/');
+ SELECT regproc('pg_catalog.now');
+ SELECT regclass('pg_catalog.pg_class');
+ SELECT regtype('pg_catalog.int4');
+ 
+ SELECT to_regoper('pg_catalog.||/');
+ SELECT to_regproc('pg_catalog.now');
+ SELECT to_regclass('pg_catalog.pg_class');
+ SELECT to_regtype('pg_catalog.int4');
+ 
+ /* If objects don't exist, raise errors. */
+ 
+ -- without schemaname
+ 
+ SELECT regoper('||//');
+ SELECT regproc('know');
+ SELECT regclass('pg_classes');
+ SELECT regtype('int3');
+ 
+ -- with schemaname
+ 
+ SELECT regoper('ng_catalog.||/');
+ SELECT regproc('ng_catalog.now');
+ SELECT regclass('ng_catalog.pg_class');
+ SELECT regtype('ng_catalog.int4');
+ 
+ /* If objects don't exist, return NULL with no error. */
+ 
+ -- without schemaname
+ 
+ SELECT to_regoper('||//');
+ SELECT to_regproc('know');
+ SELECT to_regclass('pg_classes');
+ SELECT to_regtype('int3');
+ 
+ -- with schemaname
+ 
+ SELECT to_regoper('ng_catalog.||/');
+ SELECT to_regproc('ng_catalog.now');
+ SELECT to_regclass('ng_catalog.pg_class');
+ SELECT to_regtype('ng_catalog.int4');

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 33e093e..e742181 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -15288,10 +15288,18 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
    </indexterm>
 
    <indexterm>
+    <primary>to_regprocedure</primary>
+   </indexterm>
+
+   <indexterm>
     <primary>to_regoper</primary>
    </indexterm>
 
    <indexterm>
+    <primary>to_regoperator</primary>
+   </indexterm>
+
+   <indexterm>
     <primary>to_regtype</primary>
    </indexterm>
 
@@ -15476,11 +15484,21 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
        <entry>get the oid of the named function</entry>
       </row>
       <row>
+       <entry><literal><function>to_regprocedure(<parameter>func_name</parameter>)</function></literal></entry>
+       <entry><type>regprocedure</type></entry>
+       <entry>get the oid of the named function</entry>
+      </row>
+      <row>
        <entry><literal><function>to_regoper(<parameter>operator_name</parameter>)</function></literal></entry>
        <entry><type>regoper</type></entry>
        <entry>get the oid of the named operator</entry>
       </row>
       <row>
+       <entry><literal><function>to_regoperator(<parameter>operator_name</parameter>)</function></literal></entry>
+       <entry><type>regoperator</type></entry>
+       <entry>get the oid of the named operator</entry>
+      </row>
+      <row>
        <entry><literal><function>to_regtype(<parameter>type_name</parameter>)</function></literal></entry>
        <entry><type>regtype</type></entry>
        <entry>get the oid of the named type</entry>
@@ -15652,10 +15670,12 @@ SELECT collation for ('foo' COLLATE "de_DE");
 
   <para>
    The <function>to_regclass</function>, <function>to_regproc</function>,
-   <function>to_regoper</function> and <function>to_regtype</function>
-   translate relation, function, operator, and type names to objects of
-   type <type>regclass</>, <type>regproc</>, <type>regoper</> and
-   <type>regtype</>, respectively.  These functions differ from a cast from
+   <function>to_regprocedure</function>, <function>to_regoper</function>,
+   <function>to_regoperator</function>, and <function>to_regtype</function>
+   functions translate relation, function, operator, and type names to objects
+   of type <type>regclass</>, <type>regproc</>, <type>regprocedure</type>,
+   <type>regoper</>, <type>regoperator</type>, and <type>regtype</>,
+   respectively.  These functions differ from a cast from
    text in that they don't accept a numeric OID, and that they return null
    rather than throwing an error if the name is not found (or, for
    <function>to_regproc</function> and <function>to_regoper</function>, if
diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
index ed2bdbf..6210f45 100644
--- a/src/backend/utils/adt/regproc.c
+++ b/src/backend/utils/adt/regproc.c
@@ -323,6 +323,38 @@ regprocedurein(PG_FUNCTION_ARGS)
 }
 
 /*
+ * to_regprocedure	- converts "proname(args)" to proc OID
+ *
+ * If the name is not found, we return NULL.
+ */
+Datum
+to_regprocedure(PG_FUNCTION_ARGS)
+{
+	char	   *pro_name = PG_GETARG_CSTRING(0);
+	List	   *names;
+	int			nargs;
+	Oid			argtypes[FUNC_MAX_ARGS];
+	FuncCandidateList clist;
+
+	/*
+	 * Parse the name and arguments, look up potential matches in the current
+	 * namespace search list, and scan to see which one exactly matches the
+	 * given argument types.	(There will not be more than one match.)
+	 */
+	parseNameAndArgTypes(pro_name, false, &names, &nargs, argtypes);
+
+	clist = FuncnameGetCandidates(names, nargs, NIL, false, false, true);
+
+	for (; clist; clist = clist->next)
+	{
+		if (memcmp(clist->args, argtypes, nargs * sizeof(Oid)) == 0)
+			PG_RETURN_OID(clist->oid);
+	}
+
+	PG_RETURN_NULL();
+}
+
+/*
  * format_procedure		- converts proc OID to "pro_name(args)"
  *
  * This exports the useful functionality of regprocedureout for use
@@ -722,6 +754,45 @@ regoperatorin(PG_FUNCTION_ARGS)
 }
 
 /*
+ * to_regoperator	- converts "oprname(args)" to operator OID
+ *
+ * If the name is not found, we return NULL.
+ */
+Datum
+to_regoperator(PG_FUNCTION_ARGS)
+{
+	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
+	Oid			result;
+	List	   *names;
+	int			nargs;
+	Oid			argtypes[FUNC_MAX_ARGS];
+
+	/*
+	 * Parse the name and arguments, look up potential matches in the current
+	 * namespace search list, and scan to see which one exactly matches the
+	 * given argument types.	(There will not be more than one match.)
+	 */
+	parseNameAndArgTypes(opr_name_or_oid, true, &names, &nargs, argtypes);
+	if (nargs == 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_PARAMETER),
+				 errmsg("missing argument"),
+				 errhint("Use NONE to denote the missing argument of a unary operator.")));
+	if (nargs != 2)
+		ereport(ERROR,
+				(errcode(ERRCODE_TOO_MANY_ARGUMENTS),
+				 errmsg("too many arguments"),
+				 errhint("Provide two argument types for operator.")));
+
+	result = OpernameGetOprid(names, argtypes[0], argtypes[1]);
+
+	if (!OidIsValid(result))
+		PG_RETURN_NULL();
+
+	PG_RETURN_OID(result);
+}
+
+/*
  * format_operator		- converts operator OID to "opr_name(args)"
  *
  * This exports the useful functionality of regoperatorout for use
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 21c17a0..fcbdbcf 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -175,6 +175,8 @@ DATA(insert OID =  45 (  regprocout		   PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0
 DESCR("I/O");
 DATA(insert OID = 3494 (  to_regproc		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 24 "2275" _null_ _null_ _null_ _null_ to_regproc _null_ _null_ _null_ ));
 DESCR("convert proname to regproc");
+DATA(insert OID = 3497 (  to_regprocedure	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2202 "2275" _null_ _null_ _null_ _null_ to_regprocedure _null_ _null_ _null_ ));
+DESCR("convert proname to regprocedure");
 DATA(insert OID =  46 (  textin			   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 25 "2275" _null_ _null_ _null_ _null_ textin _null_ _null_ _null_ ));
 DESCR("I/O");
 DATA(insert OID =  47 (  textout		   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2275 "25" _null_ _null_ _null_ _null_ textout _null_ _null_ _null_ ));
@@ -3308,6 +3310,8 @@ DATA(insert OID = 2215 (  regoperout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2
 DESCR("I/O");
 DATA(insert OID = 3492 (  to_regoper		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2203 "2275" _null_ _null_ _null_ _null_ to_regoper _null_ _null_ _null_ ));
 DESCR("convert operator name to regoper");
+DATA(insert OID = 3496 (  to_regoperator	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2204 "2275" _null_ _null_ _null_ _null_ to_regoperator _null_ _null_ _null_ ));
+DESCR("convert operator name to regoperator");
 DATA(insert OID = 2216 (  regoperatorin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2204 "2275" _null_ _null_ _null_ _null_ regoperatorin _null_ _null_ _null_ ));
 DESCR("I/O");
 DATA(insert OID = 2217 (  regoperatorout	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2204" _null_ _null_ _null_ _null_ regoperatorout _null_ _null_ _null_ ));
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index 720c831..719a108 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -598,6 +598,7 @@ extern char *regexp_fixed_prefix(text *text_re, bool case_insensitive,
 extern Datum regprocin(PG_FUNCTION_ARGS);
 extern Datum regprocout(PG_FUNCTION_ARGS);
 extern Datum to_regproc(PG_FUNCTION_ARGS);
+extern Datum to_regprocedure(PG_FUNCTION_ARGS);
 extern Datum regprocrecv(PG_FUNCTION_ARGS);
 extern Datum regprocsend(PG_FUNCTION_ARGS);
 extern Datum regprocedurein(PG_FUNCTION_ARGS);
@@ -609,6 +610,7 @@ extern Datum regoperout(PG_FUNCTION_ARGS);
 extern Datum regoperrecv(PG_FUNCTION_ARGS);
 extern Datum regopersend(PG_FUNCTION_ARGS);
 extern Datum to_regoper(PG_FUNCTION_ARGS);
+extern Datum to_regoperator(PG_FUNCTION_ARGS);
 extern Datum regoperatorin(PG_FUNCTION_ARGS);
 extern Datum regoperatorout(PG_FUNCTION_ARGS);
 extern Datum regoperatorrecv(PG_FUNCTION_ARGS);
diff --git a/src/test/regress/expected/regproc.out b/src/test/regress/expected/regproc.out
index 56ab245..3342129 100644
--- a/src/test/regress/expected/regproc.out
+++ b/src/test/regress/expected/regproc.out
@@ -9,12 +9,24 @@ SELECT regoper('||/');
  ||/
 (1 row)
 
+SELECT regoperator('+(int4,int4)');
+    regoperator     
+--------------------
+ +(integer,integer)
+(1 row)
+
 SELECT regproc('now');
  regproc 
 ---------
  now
 (1 row)
 
+SELECT regprocedure('abs(numeric)');
+ regprocedure 
+--------------
+ abs(numeric)
+(1 row)
+
 SELECT regclass('pg_class');
  regclass 
 ----------
@@ -33,12 +45,24 @@ SELECT to_regoper('||/');
  ||/
 (1 row)
 
+SELECT to_regoperator('+(int4,int4)');
+   to_regoperator   
+--------------------
+ +(integer,integer)
+(1 row)
+
 SELECT to_regproc('now');
  to_regproc 
 ------------
  now
 (1 row)
 
+SELECT to_regprocedure('abs(numeric)');
+ to_regprocedure 
+-----------------
+ abs(numeric)
+(1 row)
+
 SELECT to_regclass('pg_class');
  to_regclass 
 -------------
@@ -58,12 +82,24 @@ SELECT regoper('pg_catalog.||/');
  ||/
 (1 row)
 
+SELECT regoperator('pg_catalog.+(int4,int4)');
+    regoperator     
+--------------------
+ +(integer,integer)
+(1 row)
+
 SELECT regproc('pg_catalog.now');
  regproc 
 ---------
  now
 (1 row)
 
+SELECT regprocedure('pg_catalog.abs(numeric)');
+ regprocedure 
+--------------
+ abs(numeric)
+(1 row)
+
 SELECT regclass('pg_catalog.pg_class');
  regclass 
 ----------
@@ -88,6 +124,12 @@ SELECT to_regproc('pg_catalog.now');
  now
 (1 row)
 
+SELECT to_regprocedure('pg_catalog.abs(numeric)');
+ to_regprocedure 
+-----------------
+ abs(numeric)
+(1 row)
+
 SELECT to_regclass('pg_catalog.pg_class');
  to_regclass 
 -------------
@@ -106,10 +148,18 @@ SELECT regoper('||//');
 ERROR:  operator does not exist: ||//
 LINE 3: SELECT regoper('||//');
                        ^
+SELECT regoperator('++(int4,int4)');
+ERROR:  operator does not exist: ++(int4,int4)
+LINE 1: SELECT regoperator('++(int4,int4)');
+                           ^
 SELECT regproc('know');
 ERROR:  function "know" does not exist
 LINE 1: SELECT regproc('know');
                        ^
+SELECT regprocedure('absinthe(numeric)');
+ERROR:  function "absinthe(numeric)" does not exist
+LINE 1: SELECT regprocedure('absinthe(numeric)');
+                            ^
 SELECT regclass('pg_classes');
 ERROR:  relation "pg_classes" does not exist
 LINE 1: SELECT regclass('pg_classes');
@@ -123,10 +173,18 @@ SELECT regoper('ng_catalog.||/');
 ERROR:  schema "ng_catalog" does not exist
 LINE 1: SELECT regoper('ng_catalog.||/');
                        ^
+SELECT regoperator('ng_catalog.+(int4,int4)');
+ERROR:  operator does not exist: ng_catalog.+(int4,int4)
+LINE 1: SELECT regoperator('ng_catalog.+(int4,int4)');
+                           ^
 SELECT regproc('ng_catalog.now');
 ERROR:  schema "ng_catalog" does not exist
 LINE 1: SELECT regproc('ng_catalog.now');
                        ^
+SELECT regprocedure('ng_catalog.abs(numeric)');
+ERROR:  schema "ng_catalog" does not exist
+LINE 1: SELECT regprocedure('ng_catalog.abs(numeric)');
+                            ^
 SELECT regclass('ng_catalog.pg_class');
 ERROR:  schema "ng_catalog" does not exist
 LINE 1: SELECT regclass('ng_catalog.pg_class');
@@ -143,12 +201,24 @@ SELECT to_regoper('||//');
  
 (1 row)
 
+SELECT to_regoperator('++(int4,int4)');
+ to_regoperator 
+----------------
+ 
+(1 row)
+
 SELECT to_regproc('know');
  to_regproc 
 ------------
  
 (1 row)
 
+SELECT to_regprocedure('absinthe(numeric)');
+ to_regprocedure 
+-----------------
+ 
+(1 row)
+
 SELECT to_regclass('pg_classes');
  to_regclass 
 -------------
@@ -168,12 +238,24 @@ SELECT to_regoper('ng_catalog.||/');
  
 (1 row)
 
+SELECT to_regoperator('ng_catalog.+(int4,int4)');
+ to_regoperator 
+----------------
+ 
+(1 row)
+
 SELECT to_regproc('ng_catalog.now');
  to_regproc 
 ------------
  
 (1 row)
 
+SELECT to_regprocedure('ng_catalog.abs(numeric)');
+ to_regprocedure 
+-----------------
+ 
+(1 row)
+
 SELECT to_regclass('ng_catalog.pg_class');
  to_regclass 
 -------------
diff --git a/src/test/regress/sql/regproc.sql b/src/test/regress/sql/regproc.sql
index 1334cfb..cc90838 100644
--- a/src/test/regress/sql/regproc.sql
+++ b/src/test/regress/sql/regproc.sql
@@ -7,24 +7,31 @@
 -- without schemaname
 
 SELECT regoper('||/');
+SELECT regoperator('+(int4,int4)');
 SELECT regproc('now');
+SELECT regprocedure('abs(numeric)');
 SELECT regclass('pg_class');
 SELECT regtype('int4');
 
 SELECT to_regoper('||/');
+SELECT to_regoperator('+(int4,int4)');
 SELECT to_regproc('now');
+SELECT to_regprocedure('abs(numeric)');
 SELECT to_regclass('pg_class');
 SELECT to_regtype('int4');
 
 -- with schemaname
 
 SELECT regoper('pg_catalog.||/');
+SELECT regoperator('pg_catalog.+(int4,int4)');
 SELECT regproc('pg_catalog.now');
+SELECT regprocedure('pg_catalog.abs(numeric)');
 SELECT regclass('pg_catalog.pg_class');
 SELECT regtype('pg_catalog.int4');
 
 SELECT to_regoper('pg_catalog.||/');
 SELECT to_regproc('pg_catalog.now');
+SELECT to_regprocedure('pg_catalog.abs(numeric)');
 SELECT to_regclass('pg_catalog.pg_class');
 SELECT to_regtype('pg_catalog.int4');
 
@@ -33,14 +40,18 @@ SELECT to_regtype('pg_catalog.int4');
 -- without schemaname
 
 SELECT regoper('||//');
+SELECT regoperator('++(int4,int4)');
 SELECT regproc('know');
+SELECT regprocedure('absinthe(numeric)');
 SELECT regclass('pg_classes');
 SELECT regtype('int3');
 
 -- with schemaname
 
 SELECT regoper('ng_catalog.||/');
+SELECT regoperator('ng_catalog.+(int4,int4)');
 SELECT regproc('ng_catalog.now');
+SELECT regprocedure('ng_catalog.abs(numeric)');
 SELECT regclass('ng_catalog.pg_class');
 SELECT regtype('ng_catalog.int4');
 
@@ -49,13 +60,17 @@ SELECT regtype('ng_catalog.int4');
 -- without schemaname
 
 SELECT to_regoper('||//');
+SELECT to_regoperator('++(int4,int4)');
 SELECT to_regproc('know');
+SELECT to_regprocedure('absinthe(numeric)');
 SELECT to_regclass('pg_classes');
 SELECT to_regtype('int3');
 
 -- with schemaname
 
 SELECT to_regoper('ng_catalog.||/');
+SELECT to_regoperator('ng_catalog.+(int4,int4)');
 SELECT to_regproc('ng_catalog.now');
+SELECT to_regprocedure('ng_catalog.abs(numeric)');
 SELECT to_regclass('ng_catalog.pg_class');
 SELECT to_regtype('ng_catalog.int4');

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 0809a6d..db8691a 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -15294,10 +15294,18 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
    </indexterm>
 
    <indexterm>
+    <primary>to_regprocedure</primary>
+   </indexterm>
+
+   <indexterm>
     <primary>to_regoper</primary>
    </indexterm>
 
    <indexterm>
+    <primary>to_regoperator</primary>
+   </indexterm>
+
+   <indexterm>
     <primary>to_regtype</primary>
    </indexterm>
 
@@ -15482,11 +15490,21 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
        <entry>get the oid of the named function</entry>
       </row>
       <row>
+       <entry><literal><function>to_regprocedure(<parameter>func_name</parameter>)</function></literal></entry>
+       <entry><type>regprocedure</type></entry>
+       <entry>get the oid of the named function</entry>
+      </row>
+      <row>
        <entry><literal><function>to_regoper(<parameter>operator_name</parameter>)</function></literal></entry>
        <entry><type>regoper</type></entry>
        <entry>get the oid of the named operator</entry>
       </row>
       <row>
+       <entry><literal><function>to_regoperator(<parameter>operator_name</parameter>)</function></literal></entry>
+       <entry><type>regoperator</type></entry>
+       <entry>get the oid of the named operator</entry>
+      </row>
+      <row>
        <entry><literal><function>to_regtype(<parameter>type_name</parameter>)</function></literal></entry>
        <entry><type>regtype</type></entry>
        <entry>get the oid of the named type</entry>
@@ -15658,10 +15676,12 @@ SELECT collation for ('foo' COLLATE "de_DE");
 
   <para>
    The <function>to_regclass</function>, <function>to_regproc</function>,
-   <function>to_regoper</function> and <function>to_regtype</function>
-   translate relation, function, operator, and type names to objects of
-   type <type>regclass</>, <type>regproc</>, <type>regoper</> and
-   <type>regtype</>, respectively.  These functions differ from a cast from
+   <function>to_regprocedure</function>, <function>to_regoper</function>,
+   <function>to_regoperator</function>, and <function>to_regtype</function>
+   functions translate relation, function, operator, and type names to objects
+   of type <type>regclass</>, <type>regproc</>, <type>regprocedure</type>,
+   <type>regoper</>, <type>regoperator</type>, and <type>regtype</>,
+   respectively.  These functions differ from a cast from
    text in that they don't accept a numeric OID, and that they return null
    rather than throwing an error if the name is not found (or, for
    <function>to_regproc</function> and <function>to_regoper</function>, if
diff --git a/src/backend/utils/adt/regproc.c b/src/backend/utils/adt/regproc.c
index ed2bdbf..6210f45 100644
--- a/src/backend/utils/adt/regproc.c
+++ b/src/backend/utils/adt/regproc.c
@@ -323,6 +323,38 @@ regprocedurein(PG_FUNCTION_ARGS)
 }
 
 /*
+ * to_regprocedure	- converts "proname(args)" to proc OID
+ *
+ * If the name is not found, we return NULL.
+ */
+Datum
+to_regprocedure(PG_FUNCTION_ARGS)
+{
+	char	   *pro_name = PG_GETARG_CSTRING(0);
+	List	   *names;
+	int			nargs;
+	Oid			argtypes[FUNC_MAX_ARGS];
+	FuncCandidateList clist;
+
+	/*
+	 * Parse the name and arguments, look up potential matches in the current
+	 * namespace search list, and scan to see which one exactly matches the
+	 * given argument types.	(There will not be more than one match.)
+	 */
+	parseNameAndArgTypes(pro_name, false, &names, &nargs, argtypes);
+
+	clist = FuncnameGetCandidates(names, nargs, NIL, false, false, true);
+
+	for (; clist; clist = clist->next)
+	{
+		if (memcmp(clist->args, argtypes, nargs * sizeof(Oid)) == 0)
+			PG_RETURN_OID(clist->oid);
+	}
+
+	PG_RETURN_NULL();
+}
+
+/*
  * format_procedure		- converts proc OID to "pro_name(args)"
  *
  * This exports the useful functionality of regprocedureout for use
@@ -722,6 +754,45 @@ regoperatorin(PG_FUNCTION_ARGS)
 }
 
 /*
+ * to_regoperator	- converts "oprname(args)" to operator OID
+ *
+ * If the name is not found, we return NULL.
+ */
+Datum
+to_regoperator(PG_FUNCTION_ARGS)
+{
+	char	   *opr_name_or_oid = PG_GETARG_CSTRING(0);
+	Oid			result;
+	List	   *names;
+	int			nargs;
+	Oid			argtypes[FUNC_MAX_ARGS];
+
+	/*
+	 * Parse the name and arguments, look up potential matches in the current
+	 * namespace search list, and scan to see which one exactly matches the
+	 * given argument types.	(There will not be more than one match.)
+	 */
+	parseNameAndArgTypes(opr_name_or_oid, true, &names, &nargs, argtypes);
+	if (nargs == 1)
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_PARAMETER),
+				 errmsg("missing argument"),
+				 errhint("Use NONE to denote the missing argument of a unary operator.")));
+	if (nargs != 2)
+		ereport(ERROR,
+				(errcode(ERRCODE_TOO_MANY_ARGUMENTS),
+				 errmsg("too many arguments"),
+				 errhint("Provide two argument types for operator.")));
+
+	result = OpernameGetOprid(names, argtypes[0], argtypes[1]);
+
+	if (!OidIsValid(result))
+		PG_RETURN_NULL();
+
+	PG_RETURN_OID(result);
+}
+
+/*
  * format_operator		- converts operator OID to "opr_name(args)"
  *
  * This exports the useful functionality of regoperatorout for use
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 643408d..c77c036 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -175,6 +175,8 @@ DATA(insert OID =  45 (  regprocout		   PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0
 DESCR("I/O");
 DATA(insert OID = 3494 (  to_regproc		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 24 "2275" _null_ _null_ _null_ _null_ to_regproc _null_ _null_ _null_ ));
 DESCR("convert proname to regproc");
+DATA(insert OID = 3479 (  to_regprocedure	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2202 "2275" _null_ _null_ _null_ _null_ to_regprocedure _null_ _null_ _null_ ));
+DESCR("convert proname to regprocedure");
 DATA(insert OID =  46 (  textin			   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 25 "2275" _null_ _null_ _null_ _null_ textin _null_ _null_ _null_ ));
 DESCR("I/O");
 DATA(insert OID =  47 (  textout		   PGNSP PGUID 12 1 0 0 0 f f f f t f i 1 0 2275 "25" _null_ _null_ _null_ _null_ textout _null_ _null_ _null_ ));
@@ -3351,6 +3353,8 @@ DATA(insert OID = 2215 (  regoperout		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2
 DESCR("I/O");
 DATA(insert OID = 3492 (  to_regoper		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2203 "2275" _null_ _null_ _null_ _null_ to_regoper _null_ _null_ _null_ ));
 DESCR("convert operator name to regoper");
+DATA(insert OID = 3476 (  to_regoperator	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2204 "2275" _null_ _null_ _null_ _null_ to_regoperator _null_ _null_ _null_ ));
+DESCR("convert operator name to regoperator");
 DATA(insert OID = 2216 (  regoperatorin		PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2204 "2275" _null_ _null_ _null_ _null_ regoperatorin _null_ _null_ _null_ ));
 DESCR("I/O");
 DATA(insert OID = 2217 (  regoperatorout	PGNSP PGUID 12 1 0 0 0 f f f f t f s 1 0 2275 "2204" _null_ _null_ _null_ _null_ regoperatorout _null_ _null_ _null_ ));
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index 11ff4fd..33b6dca 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -602,6 +602,7 @@ extern char *regexp_fixed_prefix(text *text_re, bool case_insensitive,
 extern Datum regprocin(PG_FUNCTION_ARGS);
 extern Datum regprocout(PG_FUNCTION_ARGS);
 extern Datum to_regproc(PG_FUNCTION_ARGS);
+extern Datum to_regprocedure(PG_FUNCTION_ARGS);
 extern Datum regprocrecv(PG_FUNCTION_ARGS);
 extern Datum regprocsend(PG_FUNCTION_ARGS);
 extern Datum regprocedurein(PG_FUNCTION_ARGS);
@@ -613,6 +614,7 @@ extern Datum regoperout(PG_FUNCTION_ARGS);
 extern Datum regoperrecv(PG_FUNCTION_ARGS);
 extern Datum regopersend(PG_FUNCTION_ARGS);
 extern Datum to_regoper(PG_FUNCTION_ARGS);
+extern Datum to_regoperator(PG_FUNCTION_ARGS);
 extern Datum regoperatorin(PG_FUNCTION_ARGS);
 extern Datum regoperatorout(PG_FUNCTION_ARGS);
 extern Datum regoperatorrecv(PG_FUNCTION_ARGS);
diff --git a/src/test/regress/expected/regproc.out b/src/test/regress/expected/regproc.out
index 56ab245..3342129 100644
--- a/src/test/regress/expected/regproc.out
+++ b/src/test/regress/expected/regproc.out
@@ -9,12 +9,24 @@ SELECT regoper('||/');
  ||/
 (1 row)
 
+SELECT regoperator('+(int4,int4)');
+    regoperator     
+--------------------
+ +(integer,integer)
+(1 row)
+
 SELECT regproc('now');
  regproc 
 ---------
  now
 (1 row)
 
+SELECT regprocedure('abs(numeric)');
+ regprocedure 
+--------------
+ abs(numeric)
+(1 row)
+
 SELECT regclass('pg_class');
  regclass 
 ----------
@@ -33,12 +45,24 @@ SELECT to_regoper('||/');
  ||/
 (1 row)
 
+SELECT to_regoperator('+(int4,int4)');
+   to_regoperator   
+--------------------
+ +(integer,integer)
+(1 row)
+
 SELECT to_regproc('now');
  to_regproc 
 ------------
  now
 (1 row)
 
+SELECT to_regprocedure('abs(numeric)');
+ to_regprocedure 
+-----------------
+ abs(numeric)
+(1 row)
+
 SELECT to_regclass('pg_class');
  to_regclass 
 -------------
@@ -58,12 +82,24 @@ SELECT regoper('pg_catalog.||/');
  ||/
 (1 row)
 
+SELECT regoperator('pg_catalog.+(int4,int4)');
+    regoperator     
+--------------------
+ +(integer,integer)
+(1 row)
+
 SELECT regproc('pg_catalog.now');
  regproc 
 ---------
  now
 (1 row)
 
+SELECT regprocedure('pg_catalog.abs(numeric)');
+ regprocedure 
+--------------
+ abs(numeric)
+(1 row)
+
 SELECT regclass('pg_catalog.pg_class');
  regclass 
 ----------
@@ -88,6 +124,12 @@ SELECT to_regproc('pg_catalog.now');
  now
 (1 row)
 
+SELECT to_regprocedure('pg_catalog.abs(numeric)');
+ to_regprocedure 
+-----------------
+ abs(numeric)
+(1 row)
+
 SELECT to_regclass('pg_catalog.pg_class');
  to_regclass 
 -------------
@@ -106,10 +148,18 @@ SELECT regoper('||//');
 ERROR:  operator does not exist: ||//
 LINE 3: SELECT regoper('||//');
                        ^
+SELECT regoperator('++(int4,int4)');
+ERROR:  operator does not exist: ++(int4,int4)
+LINE 1: SELECT regoperator('++(int4,int4)');
+                           ^
 SELECT regproc('know');
 ERROR:  function "know" does not exist
 LINE 1: SELECT regproc('know');
                        ^
+SELECT regprocedure('absinthe(numeric)');
+ERROR:  function "absinthe(numeric)" does not exist
+LINE 1: SELECT regprocedure('absinthe(numeric)');
+                            ^
 SELECT regclass('pg_classes');
 ERROR:  relation "pg_classes" does not exist
 LINE 1: SELECT regclass('pg_classes');
@@ -123,10 +173,18 @@ SELECT regoper('ng_catalog.||/');
 ERROR:  schema "ng_catalog" does not exist
 LINE 1: SELECT regoper('ng_catalog.||/');
                        ^
+SELECT regoperator('ng_catalog.+(int4,int4)');
+ERROR:  operator does not exist: ng_catalog.+(int4,int4)
+LINE 1: SELECT regoperator('ng_catalog.+(int4,int4)');
+                           ^
 SELECT regproc('ng_catalog.now');
 ERROR:  schema "ng_catalog" does not exist
 LINE 1: SELECT regproc('ng_catalog.now');
                        ^
+SELECT regprocedure('ng_catalog.abs(numeric)');
+ERROR:  schema "ng_catalog" does not exist
+LINE 1: SELECT regprocedure('ng_catalog.abs(numeric)');
+                            ^
 SELECT regclass('ng_catalog.pg_class');
 ERROR:  schema "ng_catalog" does not exist
 LINE 1: SELECT regclass('ng_catalog.pg_class');
@@ -143,12 +201,24 @@ SELECT to_regoper('||//');
  
 (1 row)
 
+SELECT to_regoperator('++(int4,int4)');
+ to_regoperator 
+----------------
+ 
+(1 row)
+
 SELECT to_regproc('know');
  to_regproc 
 ------------
  
 (1 row)
 
+SELECT to_regprocedure('absinthe(numeric)');
+ to_regprocedure 
+-----------------
+ 
+(1 row)
+
 SELECT to_regclass('pg_classes');
  to_regclass 
 -------------
@@ -168,12 +238,24 @@ SELECT to_regoper('ng_catalog.||/');
  
 (1 row)
 
+SELECT to_regoperator('ng_catalog.+(int4,int4)');
+ to_regoperator 
+----------------
+ 
+(1 row)
+
 SELECT to_regproc('ng_catalog.now');
  to_regproc 
 ------------
  
 (1 row)
 
+SELECT to_regprocedure('ng_catalog.abs(numeric)');
+ to_regprocedure 
+-----------------
+ 
+(1 row)
+
 SELECT to_regclass('ng_catalog.pg_class');
  to_regclass 
 -------------
diff --git a/src/test/regress/sql/regproc.sql b/src/test/regress/sql/regproc.sql
index 1334cfb..cc90838 100644
--- a/src/test/regress/sql/regproc.sql
+++ b/src/test/regress/sql/regproc.sql
@@ -7,24 +7,31 @@
 -- without schemaname
 
 SELECT regoper('||/');
+SELECT regoperator('+(int4,int4)');
 SELECT regproc('now');
+SELECT regprocedure('abs(numeric)');
 SELECT regclass('pg_class');
 SELECT regtype('int4');
 
 SELECT to_regoper('||/');
+SELECT to_regoperator('+(int4,int4)');
 SELECT to_regproc('now');
+SELECT to_regprocedure('abs(numeric)');
 SELECT to_regclass('pg_class');
 SELECT to_regtype('int4');
 
 -- with schemaname
 
 SELECT regoper('pg_catalog.||/');
+SELECT regoperator('pg_catalog.+(int4,int4)');
 SELECT regproc('pg_catalog.now');
+SELECT regprocedure('pg_catalog.abs(numeric)');
 SELECT regclass('pg_catalog.pg_class');
 SELECT regtype('pg_catalog.int4');
 
 SELECT to_regoper('pg_catalog.||/');
 SELECT to_regproc('pg_catalog.now');
+SELECT to_regprocedure('pg_catalog.abs(numeric)');
 SELECT to_regclass('pg_catalog.pg_class');
 SELECT to_regtype('pg_catalog.int4');
 
@@ -33,14 +40,18 @@ SELECT to_regtype('pg_catalog.int4');
 -- without schemaname
 
 SELECT regoper('||//');
+SELECT regoperator('++(int4,int4)');
 SELECT regproc('know');
+SELECT regprocedure('absinthe(numeric)');
 SELECT regclass('pg_classes');
 SELECT regtype('int3');
 
 -- with schemaname
 
 SELECT regoper('ng_catalog.||/');
+SELECT regoperator('ng_catalog.+(int4,int4)');
 SELECT regproc('ng_catalog.now');
+SELECT regprocedure('ng_catalog.abs(numeric)');
 SELECT regclass('ng_catalog.pg_class');
 SELECT regtype('ng_catalog.int4');
 
@@ -49,13 +60,17 @@ SELECT regtype('ng_catalog.int4');
 -- without schemaname
 
 SELECT to_regoper('||//');
+SELECT to_regoperator('++(int4,int4)');
 SELECT to_regproc('know');
+SELECT to_regprocedure('absinthe(numeric)');
 SELECT to_regclass('pg_classes');
 SELECT to_regtype('int3');
 
 -- with schemaname
 
 SELECT to_regoper('ng_catalog.||/');
+SELECT to_regoperator('ng_catalog.+(int4,int4)');
 SELECT to_regproc('ng_catalog.now');
+SELECT to_regprocedure('ng_catalog.abs(numeric)');
 SELECT to_regclass('ng_catalog.pg_class');
 SELECT to_regtype('ng_catalog.int4');