Avoid reversing user-given order of WHERE clauses while attaching clauses

to specific base or join RelOptInfo nodes during planning.  This preserves
the more-intuitive behavior of 7.0.* --- if you write an expensive clause
(such as a sub-select) last, it should get evaluated last.  Someday we
ought to try to have some intelligence about the order of evaluation of
WHERE clauses, but for now we should not override what the user wrote.

diff --git a/src/backend/optimizer/plan/initsplan.c b/src/backend/optimizer/plan/initsplan.c
index 2b2ebf238fefbe702ddb211a6064a16740b18f2e..7c3e15a8f88d81b206e4d3f618eae9658294ad6a 100644 (file)
--- a/src/backend/optimizer/plan/initsplan.c
+++ b/src/backend/optimizer/plan/initsplan.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/optimizer/plan/initsplan.c,v 1.58 2001/03/22 03:59:36 momjian Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/optimizer/plan/initsplan.c,v 1.59 2001/04/16 19:44:10 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -444,8 +444,8 @@ distribute_qual_to_rels(Query *root, Node *clause,
                 */
                RelOptInfo *rel = get_base_rel(root, lfirsti(relids));
 
-               rel->baserestrictinfo = lcons(restrictinfo,
-                                                                         rel->baserestrictinfo);
+               rel->baserestrictinfo = lappend(rel->baserestrictinfo,
+                                                                               restrictinfo);
 
                /*
                 * Check for a "mergejoinable" clause even though it's not a join
@@ -549,8 +549,8 @@ add_join_info_to_rels(Query *root, RestrictInfo *restrictinfo,
                 */
                joininfo = find_joininfo_node(get_base_rel(root, cur_relid),
                                                                          unjoined_relids);
-               joininfo->jinfo_restrictinfo = lcons(restrictinfo,
-                                                                                  joininfo->jinfo_restrictinfo);
+               joininfo->jinfo_restrictinfo = lappend(joininfo->jinfo_restrictinfo,
+                                                                                          restrictinfo);
        }
 }