From c5ff3ff49229e8fb7da0e46b463bfc9b12219078 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Fri, 8 Apr 2011 16:11:04 -0400
Subject: [PATCH] Avoid an unnecessary syscache lookup in parse_coerce.c.

All the other fields of the constant are being extracted from the syscache
entry we already have, so handle collation similarly.  (There don't seem
to be any other uses for the new function at the moment.)
---
 src/backend/parser/parse_coerce.c |  2 +-
 src/backend/parser/parse_type.c   | 16 +++++++++++++---
 src/include/parser/parse_type.h   |  1 +
 3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/src/backend/parser/parse_coerce.c b/src/backend/parser/parse_coerce.c
index dd3e748c9f..895c3ad985 100644
--- a/src/backend/parser/parse_coerce.c
+++ b/src/backend/parser/parse_coerce.c
@@ -219,7 +219,7 @@ coerce_type(ParseState *pstate, Node *node,
 
 		newcon->consttype = baseTypeId;
 		newcon->consttypmod = inputTypeMod;
-		newcon->constcollid = get_typcollation(newcon->consttype);
+		newcon->constcollid = typeTypeCollation(targetType);
 		newcon->constlen = typeLen(targetType);
 		newcon->constbyval = typeByVal(targetType);
 		newcon->constisnull = con->constisnull;
diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
index f413593f60..ac62cbc8c3 100644
--- a/src/backend/parser/parse_type.c
+++ b/src/backend/parser/parse_type.c
@@ -528,7 +528,7 @@ typeLen(Type t)
 	return typ->typlen;
 }
 
-/* given type (as type struct), return the value of its 'byval' attribute.*/
+/* given type (as type struct), return its 'byval' attribute */
 bool
 typeByVal(Type t)
 {
@@ -538,7 +538,7 @@ typeByVal(Type t)
 	return typ->typbyval;
 }
 
-/* given type (as type struct), return the name of type */
+/* given type (as type struct), return the type's name */
 char *
 typeTypeName(Type t)
 {
@@ -549,16 +549,26 @@ typeTypeName(Type t)
 	return pstrdup(NameStr(typ->typname));
 }
 
+/* given type (as type struct), return its 'typrelid' attribute */
 Oid
 typeTypeRelid(Type typ)
 {
 	Form_pg_type typtup;
 
 	typtup = (Form_pg_type) GETSTRUCT(typ);
-
 	return typtup->typrelid;
 }
 
+/* given type (as type struct), return its 'typcollation' attribute */
+Oid
+typeTypeCollation(Type typ)
+{
+	Form_pg_type typtup;
+
+	typtup = (Form_pg_type) GETSTRUCT(typ);
+	return typtup->typcollation;
+}
+
 /*
  * Given a type structure and a string, returns the internal representation
  * of that string.	The "string" can be NULL to perform conversion of a NULL
diff --git a/src/include/parser/parse_type.h b/src/include/parser/parse_type.h
index 92c9ecba4a..509e3b7f11 100644
--- a/src/include/parser/parse_type.h
+++ b/src/include/parser/parse_type.h
@@ -40,6 +40,7 @@ extern int16 typeLen(Type t);
 extern bool typeByVal(Type t);
 extern char *typeTypeName(Type t);
 extern Oid	typeTypeRelid(Type typ);
+extern Oid	typeTypeCollation(Type typ);
 extern Datum stringTypeDatum(Type tp, char *string, int32 atttypmod);
 
 extern Oid	typeidTypeRelid(Oid type_id);