Remove bogus code in oper_exact --- if it didn't find an exact

match then it tried for a self-commutative operator with the reversed input
data types.  This is pretty silly; there could never be such an operator,
except maybe in binary-compatible-type scenarios, and we have oper_inexact
for that.  Besides which, the oprsanity regress test would complain about
such an operator.  Remove nonfunctional code and simplify routine calling
convention accordingly.

Author: tglsfdc

src/backend/parser/parse_node.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_node.c,v 1.30 1999/08/22 20:15:04 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_node.c,v 1.31 1999/08/23 23:48:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -31,10 +31,6 @@
 #include "utils/syscache.h"
 
 static void disallow_setop(char *op, Type optype, Node *operand);
-static Node *make_operand(char *opname,
-			 Node *tree,
-			 Oid orig_typeId,
-			 Oid true_typeId);
 
 /* make_parsestate()
  * Allocate and initialize a new ParseState.
@@ -58,31 +54,31 @@ make_parsestate(ParseState *parentParseState)
 /* make_operand()
  * Ensure argument type match by forcing conversion of constants.
  */
-static Node *
+Node *
 make_operand(char *opname,
 			 Node *tree,
 			 Oid orig_typeId,
-			 Oid true_typeId)
+			 Oid target_typeId)
 {
 	Node	   *result;
-	Type		true_type;
+	Type		target_type;
 
 	if (tree != NULL)
 	{
 		result = tree;
-		true_type = typeidType(true_typeId);
-		disallow_setop(opname, true_type, result);
+		target_type = typeidType(target_typeId);
+		disallow_setop(opname, target_type, result);
 
 		/* must coerce? */
-		if (true_typeId != orig_typeId)
-			result = coerce_type(NULL, tree, orig_typeId, true_typeId, -1);
+		if (target_typeId != orig_typeId)
+			result = coerce_type(NULL, tree, orig_typeId, target_typeId, -1);
 	}
 	/* otherwise, this is a NULL value */
 	else
 	{
 		Const	   *con = makeNode(Const);
 
-		con->consttype = true_typeId;
+		con->consttype = target_typeId;
 		con->constlen = 0;
 		con->constvalue = (Datum) (struct varlena *) NULL;
 		con->constisnull = true;
@@ -128,47 +124,31 @@ make_op(char *opname, Node *ltree, Node *rtree)
 			   *right;
 	Expr	   *result;
 
+	ltypeId = (ltree == NULL) ? UNKNOWNOID : exprType(ltree);
+	rtypeId = (rtree == NULL) ? UNKNOWNOID : exprType(rtree);
+
 	/* right operator? */
 	if (rtree == NULL)
 	{
-		ltypeId = (ltree == NULL) ? UNKNOWNOID : exprType(ltree);
 		tup = right_oper(opname, ltypeId);
 		opform = (Form_pg_operator) GETSTRUCT(tup);
 		left = make_operand(opname, ltree, ltypeId, opform->oprleft);
 		right = NULL;
-
 	}
 
 	/* left operator? */
 	else if (ltree == NULL)
 	{
-		rtypeId = (rtree == NULL) ? UNKNOWNOID : exprType(rtree);
 		tup = left_oper(opname, rtypeId);
 		opform = (Form_pg_operator) GETSTRUCT(tup);
 		right = make_operand(opname, rtree, rtypeId, opform->oprright);
 		left = NULL;
-
 	}
 
 	/* otherwise, binary operator */
 	else
 	{
-		/* binary operator */
-		ltypeId = (ltree == NULL) ? UNKNOWNOID : exprType(ltree);
-		rtypeId = (rtree == NULL) ? UNKNOWNOID : exprType(rtree);
-
-		/* check for exact match on this operator... */
-		if (HeapTupleIsValid(tup = oper_exact(opname, ltypeId, rtypeId, &ltree, &rtree, TRUE)))
-		{
-			ltypeId = exprType(ltree);
-			rtypeId = exprType(rtree);
-		}
-		/* try to find a match on likely candidates... */
-		else if (!HeapTupleIsValid(tup = oper_inexact(opname, ltypeId, rtypeId, &ltree, &rtree, FALSE)))
-		{
-			/* Won't return from oper_inexact() without a candidate... */
-		}
-
+		tup = oper(opname, ltypeId, rtypeId, FALSE);
 		opform = (Form_pg_operator) GETSTRUCT(tup);
 		left = make_operand(opname, ltree, ltypeId, opform->oprleft);
 		right = make_operand(opname, rtree, rtypeId, opform->oprright);

src/backend/parser/parse_oper.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_oper.c,v 1.29 1999/07/17 20:17:25 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_oper.c,v 1.30 1999/08/23 23:48:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -25,6 +25,8 @@
 
 static Oid *oper_select_candidate(int nargs, Oid *input_typeids,
 					  CandidateList candidates);
+static Operator oper_exact(char *op, Oid arg1, Oid arg2);
+static Operator oper_inexact(char *op, Oid arg1, Oid arg2);
 static int binary_oper_get_candidates(char *opname,
 						   Oid leftTypeId,
 						   Oid rightTypeId,
@@ -376,15 +378,14 @@ oper_select_candidate(int nargs,
 
 
 /* oper_exact()
- * Given operator, and arguments, return oper struct.
+ * Given operator, and arguments, return oper struct or NULL.
  * Inputs:
  * arg1, arg2: Type IDs
  */
-Operator
-oper_exact(char *op, Oid arg1, Oid arg2, Node **ltree, Node **rtree, bool noWarnings)
+static Operator
+oper_exact(char *op, Oid arg1, Oid arg2)
 {
 	HeapTuple	tup;
-	Node	   *tree;
 
 	/* Unspecified type for one of the arguments? then use the other */
 	if ((arg1 == UNKNOWNOID) && (arg2 != InvalidOid))
@@ -398,51 +399,17 @@ oper_exact(char *op, Oid arg1, Oid arg2, Node **ltree, Node **rtree, bool noWarn
 							  ObjectIdGetDatum(arg2),
 							  CharGetDatum('b'));
 
-	/*
-	 * Did not find anything? then try flipping arguments on a commutative
-	 * operator...
-	 */
-	if (!HeapTupleIsValid(tup) && (arg1 != arg2))
-	{
-		tup = SearchSysCacheTuple(OPRNAME,
-								  PointerGetDatum(op),
-								  ObjectIdGetDatum(arg2),
-								  ObjectIdGetDatum(arg1),
-								  CharGetDatum('b'));
-
-		if (HeapTupleIsValid(tup))
-		{
-			Form_pg_operator opform;
-
-			opform = (Form_pg_operator) GETSTRUCT(tup);
-			if (opform->oprcom == tup->t_data->t_oid)
-			{
-				if ((ltree != NULL) && (rtree != NULL))
-				{
-					tree = *ltree;
-					*ltree = *rtree;
-					*rtree = tree;
-				}
-			}
-			/* disable for now... - thomas 1998-05-14 */
-			else
-				tup = NULL;
-		}
-		if (!HeapTupleIsValid(tup) && (!noWarnings))
-			op_error(op, arg1, arg2);
-	}
-
-	return tup;
+	return (Operator) tup;
 }	/* oper_exact() */
 
 
 /* oper_inexact()
- * Given operator, types of arg1, and arg2, return oper struct.
+ * Given operator, types of arg1, and arg2, return oper struct or NULL.
  * Inputs:
  * arg1, arg2: Type IDs
  */
-Operator
-oper_inexact(char *op, Oid arg1, Oid arg2, Node **ltree, Node **rtree, bool noWarnings)
+static Operator
+oper_inexact(char *op, Oid arg1, Oid arg2)
 {
 	HeapTuple	tup;
 	CandidateList candidates;
@@ -458,13 +425,9 @@ oper_inexact(char *op, Oid arg1, Oid arg2, Node **ltree, Node **rtree, bool noWa
 
 	ncandidates = binary_oper_get_candidates(op, arg1, arg2, &candidates);
 
-	/* No operators found? Then throw error or return null... */
+	/* No operators found? Then return null... */
 	if (ncandidates == 0)
-	{
-		if (!noWarnings)
-			op_error(op, arg1, arg2);
 		return NULL;
-	}
 
 	/* Or found exactly one? Then proceed... */
 	else if (ncandidates == 1)
@@ -493,18 +456,6 @@ oper_inexact(char *op, Oid arg1, Oid arg2, Node **ltree, Node **rtree, bool noWa
 		}
 		else
 			tup = NULL;
-
-		/* Could not choose one, for whatever reason... */
-		if (!HeapTupleIsValid(tup))
-		{
-			if (!noWarnings)
-			{
-				elog(ERROR, "Unable to identify an operator '%s' for types '%s' and '%s'"
-					 "\n\tYou will have to retype this query using an explicit cast",
-					 op, typeTypeName(typeidType(arg1)), typeTypeName(typeidType(arg2)));
-			}
-			return NULL;
-		}
 	}
 	return (Operator) tup;
 }	/* oper_inexact() */
@@ -521,17 +472,16 @@ oper(char *opname, Oid ltypeId, Oid rtypeId, bool noWarnings)
 	HeapTuple	tup;
 
 	/* check for exact match on this operator... */
-	if (HeapTupleIsValid(tup = oper_exact(opname, ltypeId, rtypeId, NULL, NULL, TRUE)))
+	if (HeapTupleIsValid(tup = oper_exact(opname, ltypeId, rtypeId)))
 	{
 	}
 	/* try to find a match on likely candidates... */
-	else if (HeapTupleIsValid(tup = oper_inexact(opname, ltypeId, rtypeId, NULL, NULL, TRUE)))
+	else if (HeapTupleIsValid(tup = oper_inexact(opname, ltypeId, rtypeId)))
 	{
 	}
 	else if (!noWarnings)
 	{
-		elog(ERROR, "Unable to identify a binary operator '%s' for types %s and %s",
-			 opname, typeTypeName(typeidType(ltypeId)), typeTypeName(typeidType(rtypeId)));
+		op_error(opname, ltypeId, rtypeId);
 	}
 
 	return (Operator) tup;
@@ -741,8 +691,7 @@ op_error(char *op, Oid arg1, Oid arg2)
 			 "\n\tProbably a bad attribute name", op);
 	}
 
-	elog(ERROR, "There is no operator '%s' for types '%s' and '%s'"
-		 "\n\tYou will either have to retype this query using an explicit cast,"
-	 "\n\tor you will have to define the operator using CREATE OPERATOR",
+	elog(ERROR, "Unable to identify an operator '%s' for types '%s' and '%s'"
+		 "\n\tYou will have to retype this query using an explicit cast",
 		 op, typeTypeName(tp1), typeTypeName(tp2));
 }

src/include/parser/parse_node.h

@@ -5,7 +5,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: parse_node.h,v 1.15 1999/07/19 00:26:17 tgl Exp $
+ * $Id: parse_node.h,v 1.16 1999/08/23 23:48:37 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -33,6 +33,8 @@ typedef struct ParseState
 
 extern ParseState *make_parsestate(ParseState *parentParseState);
 extern Expr *make_op(char *opname, Node *ltree, Node *rtree);
+extern Node *make_operand(char *opname, Node *tree,
+						  Oid orig_typeId, Oid target_typeId);
 extern Var *make_var(ParseState *pstate, Oid relid, char *refname,
 		 char *attrname);
 extern ArrayRef *transformArraySubscripts(ParseState *pstate,

src/include/parser/parse_oper.h

@@ -6,7 +6,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: parse_oper.h,v 1.8 1999/07/15 15:21:27 momjian Exp $
+ * $Id: parse_oper.h,v 1.9 1999/08/23 23:48:38 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -23,7 +23,4 @@ extern Operator oper(char *op, Oid arg1, Oid arg2, bool noWarnings);
 extern Operator right_oper(char *op, Oid arg);
 extern Operator left_oper(char *op, Oid arg);
 
-extern Operator oper_exact(char *op, Oid arg1, Oid arg2, Node **ltree, Node **rtree, bool noWarnings);
-extern Operator oper_inexact(char *op, Oid arg1, Oid arg2, Node **ltree, Node **rtree, bool noWarnings);
-
 #endif	 /* PARSE_OPER_H */