Cause CHAR(n) to TEXT or VARCHAR conversion to automatically strip trailing

blanks, in hopes of reducing the surprise factor for newbies.  Remove
redundant operators for VARCHAR (it depends wholly on TEXT operations now).
Clean up resolution of ambiguous operators/functions to avoid surprising
choices for domains: domains are treated as equivalent to their base types
and binary-coercibility is no longer considered a preference item when
choosing among multiple operators/functions.  IsBinaryCoercible now correctly
reflects the notion that you need *only* relabel the type to get from type
A to type B: that is, a domain is binary-coercible to its base type, but
not vice versa.  Various marginal cleanup, including merging the essentially
duplicate resolution code in parse_func.c and parse_oper.c.  Improve opr_sanity
regression test to understand about binary compatibility (using pg_cast),
and fix a couple of small errors in the catalogs revealed thereby.
Restructure "special operator" handling to fetch operators via index opclasses
rather than hardwiring assumptions about names (cleans up the pattern_ops
stuff a little).

1 files changed, 28 insertions, 1 deletions

diff --git a/src/backend/utils/cache/lsyscache.c b/src/backend/utils/cache/lsyscache.c
index 19178cc5243..fcd9dc2f59b 100644
--- a/src/backend/utils/cache/lsyscache.c
+++ b/src/backend/utils/cache/lsyscache.c
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/utils/cache/lsyscache.c,v 1.94 2003/05/13 04:38:58 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/utils/cache/lsyscache.c,v 1.95 2003/05/26 00:11:27 tgl Exp $
  *
  * NOTES
  *	  Eventually, the index information should go through here, too.
@@ -80,6 +80,33 @@ op_requires_recheck(Oid opno, Oid opclass)
 	return result;
 }
 
+/*
+ * get_opclass_member
+ *		Get the OID of the operator that implements the specified strategy
+ *		for the specified opclass.
+ *
+ * Returns InvalidOid if there is no pg_amop entry for the given keys.
+ */
+Oid
+get_opclass_member(Oid opclass, int16 strategy)
+{
+	HeapTuple	tp;
+	Form_pg_amop amop_tup;
+	Oid			result;
+
+	tp = SearchSysCache(AMOPSTRATEGY,
+						ObjectIdGetDatum(opclass),
+						Int16GetDatum(strategy),
+						0, 0);
+	if (!HeapTupleIsValid(tp))
+		return InvalidOid;
+	amop_tup = (Form_pg_amop) GETSTRUCT(tp);
+	result = amop_tup->amopopr;
+	ReleaseSysCache(tp);
+	return result;
+}
+
+
 /*				---------- ATTRIBUTE CACHES ----------					 */
 
 /*