6 files changed, 23 insertions, 19 deletions

diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 373d2adc71c..1633499f939 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -1993,8 +1993,7 @@ opt_collate_clause:
 				{
 					CollateClause *n = makeNode(CollateClause);
 					n->arg = NULL;
-					n->collnames = $2;
-					n->collOid = InvalidOid;
+					n->collname = $2;
 					n->location = @1;
 					$$ = (Node *) n;
 				}
@@ -2537,8 +2536,7 @@ ColConstraint:
 					 */
 					CollateClause *n = makeNode(CollateClause);
 					n->arg = NULL;
-					n->collnames = $2;
-					n->collOid = InvalidOid;
+					n->collname = $2;
 					n->location = @1;
 					$$ = (Node *) n;
 				}
@@ -9690,8 +9688,8 @@ a_expr:		c_expr									{ $$ = $1; }
 			| a_expr COLLATE any_name
 				{
 					CollateClause *n = makeNode(CollateClause);
-					n->arg = (Expr *) $1;
-					n->collnames = $3;
+					n->arg = $1;
+					n->collname = $3;
 					n->location = @2;
 					$$ = (Node *) n;
 				}
diff --git a/src/backend/parser/parse_coerce.c b/src/backend/parser/parse_coerce.c
index 2fd808d26b2..6aff34dd90d 100644
--- a/src/backend/parser/parse_coerce.c
+++ b/src/backend/parser/parse_coerce.c
@@ -279,11 +279,17 @@ coerce_type(ParseState *pstate, Node *node,
 		if (result)
 			return result;
 	}
-	if (IsA(node, CollateClause))
+	if (IsA(node, CollateExpr))
 	{
-		CollateClause *cc = (CollateClause *) node;
+		/*
+		 * XXX very ugly kluge to push the coercion underneath the CollateExpr.
+		 * This needs to be rethought, as it almost certainly doesn't cover
+		 * all cases.
+		 */
+		CollateExpr *cc = (CollateExpr *) node;
 
-		cc->arg = (Expr *) coerce_type(pstate, (Node *) cc->arg, inputTypeId, targetTypeId, targetTypeMod,
+		cc->arg = (Expr *) coerce_type(pstate, (Node *) cc->arg,
+									   inputTypeId, targetTypeId, targetTypeMod,
 									   ccontext, cformat, location);
 		return (Node *) cc;
 	}
@@ -2121,7 +2127,7 @@ select_common_collation(ParseState *pstate, List *exprs, bool none_ok)
 	{
 		Node	   *pexpr = (Node *) lfirst(lc);
 		Oid			pcoll = exprCollation(pexpr);
-		bool		pexplicit = IsA(pexpr, CollateClause);
+		bool		pexplicit = IsA(pexpr, CollateExpr);
 
 		if (pcoll && pexplicit)
 		{
@@ -2130,7 +2136,7 @@ select_common_collation(ParseState *pstate, List *exprs, bool none_ok)
 			{
 				Node	   *nexpr = (Node *) lfirst(lc2);
 				Oid			ncoll = exprCollation(nexpr);
-				bool		nexplicit = IsA(nexpr, CollateClause);
+				bool		nexplicit = IsA(nexpr, CollateExpr);
 
 				if (!ncoll || !nexplicit)
 					continue;
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index 7a4f8cc2497..17bd2bf50ae 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -318,6 +318,7 @@ transformExpr(ParseState *pstate, Node *expr)
 		case T_CoerceViaIO:
 		case T_ArrayCoerceExpr:
 		case T_ConvertRowtypeExpr:
+		case T_CollateExpr:
 		case T_CaseTestExpr:
 		case T_ArrayExpr:
 		case T_CoerceToDomain:
@@ -2103,11 +2104,11 @@ transformTypeCast(ParseState *pstate, TypeCast *tc)
 static Node *
 transformCollateClause(ParseState *pstate, CollateClause *c)
 {
-	CollateClause *newc;
+	CollateExpr *newc;
 	Oid		argtype;
 
-	newc = makeNode(CollateClause);
-	newc->arg = (Expr *) transformExpr(pstate, (Node *) c->arg);
+	newc = makeNode(CollateExpr);
+	newc->arg = (Expr *) transformExpr(pstate, c->arg);
 
 	argtype = exprType((Node *) newc->arg);
 	/*
@@ -2121,8 +2122,7 @@ transformCollateClause(ParseState *pstate, CollateClause *c)
 						format_type_be(argtype)),
 				 parser_errposition(pstate, c->location)));
 
-	newc->collOid = LookupCollation(pstate, c->collnames, c->location);
-	newc->collnames = c->collnames;
+	newc->collOid = LookupCollation(pstate, c->collname, c->location);
 	newc->location = c->location;
 
 	return (Node *) newc;
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index c0eaea71a66..fd1529fb3f9 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1583,7 +1583,7 @@ FigureColnameInternal(Node *node, char **name)
 			}
 			break;
 		case T_CollateClause:
-			return FigureColnameInternal((Node *) ((CollateClause *) node)->arg, name);
+			return FigureColnameInternal(((CollateClause *) node)->arg, name);
 		case T_CaseExpr:
 			strength = FigureColnameInternal((Node *) ((CaseExpr *) node)->defresult,
 											 name);
diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
index 2ba9bf51816..f413593f602 100644
--- a/src/backend/parser/parse_type.c
+++ b/src/backend/parser/parse_type.c
@@ -471,7 +471,7 @@ GetColumnDefCollation(ParseState *pstate, ColumnDef *coldef, Oid typeOid)
 	{
 		/* We have a raw COLLATE clause, so look up the collation */
 		location = coldef->collClause->location;
-		result = LookupCollation(pstate, coldef->collClause->collnames,
+		result = LookupCollation(pstate, coldef->collClause->collname,
 								 location);
 	}
 	else if (OidIsValid(coldef->collOid))
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index e876853af02..06baf89886a 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -2467,7 +2467,7 @@ transformColumnType(CreateStmtContext *cxt, ColumnDef *column)
 		Oid		collOid;
 
 		collOid = LookupCollation(cxt->pstate,
-								  column->collClause->collnames,
+								  column->collClause->collname,
 								  column->collClause->location);
 		/* Complain if COLLATE is applied to an uncollatable type */
 		if (!OidIsValid(typtup->typcollation))