Major revision of sort-node handling: push knowledge of query

sort order down into planner, instead of handling it only at the very top
level of the planner.  This fixes many things.  An explicit sort is now
avoided if there is a cheaper alternative (typically an indexscan) not
only for ORDER BY, but also for the internal sort of GROUP BY.  It works
even when there is no other reason (such as a WHERE condition) to consider
the indexscan.  It works for indexes on functions.  It works for indexes
on functions, backwards.  It's just so cool...

CAUTION: I have changed the representation of SortClause nodes, therefore
THIS UPDATE BREAKS STORED RULES.  You will need to initdb.

1 files changed, 2 insertions, 3 deletions

diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c
index 344c87920bc..4a227de2c5b 100644
--- a/src/backend/parser/parse_func.c
+++ b/src/backend/parser/parse_func.c
@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_func.c,v 1.52 1999/08/16 02:08:59 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/parser/parse_func.c,v 1.53 1999/08/21 03:48:55 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -63,7 +63,6 @@ static int match_argtypes(int nargs,
 			   CandidateList function_typeids,
 			   CandidateList *candidates);
 static List *setup_tlist(char *attname, Oid relid);
-static List *setup_base_tlist(Oid typeid);
 static Oid *func_select_candidate(int nargs, Oid *input_typeids,
 					  CandidateList candidates);
 static int	agg_get_candidates(char *aggname, Oid typeId, CandidateList *candidates);
@@ -1312,7 +1311,7 @@ setup_tlist(char *attname, Oid relid)
  **		Build a tlist that extracts a base type from the tuple
  **		returned by the executor.
  */
-static List *
+List *
 setup_base_tlist(Oid typeid)
 {
 	TargetEntry *tle;