Allow the planner to collapse explicit inner JOINs together, rather than

necessarily following the JOIN syntax to develop the query plan.  The old
behavior is still available by setting GUC variable JOIN_COLLAPSE_LIMIT
to 1.  Also create a GUC variable FROM_COLLAPSE_LIMIT to control the
similar decision about when to collapse sub-SELECT lists into their parent
lists.  (This behavior existed already, but the limit was always
GEQO_THRESHOLD/2; now it's separately adjustable.)

2 files changed, 6 insertions, 8 deletions

diff --git a/src/include/optimizer/paths.h b/src/include/optimizer/paths.h
index 76285bac408..8b4f701744e 100644
--- a/src/include/optimizer/paths.h
+++ b/src/include/optimizer/paths.h
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: paths.h,v 1.64 2003/01/24 03:58:43 tgl Exp $
+ * $Id: paths.h,v 1.65 2003/01/25 23:10:30 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -18,16 +18,11 @@
 #include "nodes/relation.h"
 
 
-/* default GEQO threshold (default value for geqo_rels) */
-/* If you change this, update backend/utils/misc/postgresql.sample.conf */
-#define DEFAULT_GEQO_RELS 11
-
-
 /*
  * allpaths.c
  */
 extern bool enable_geqo;
-extern int	geqo_rels;
+extern int	geqo_threshold;
 
 extern RelOptInfo *make_one_rel(Query *root);
 extern RelOptInfo *make_fromexpr_rel(Query *root, FromExpr *from);
diff --git a/src/include/optimizer/prep.h b/src/include/optimizer/prep.h
index 17ecb4d593f..458539a8174 100644
--- a/src/include/optimizer/prep.h
+++ b/src/include/optimizer/prep.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: prep.h,v 1.34 2003/01/20 18:55:05 tgl Exp $
+ * $Id: prep.h,v 1.35 2003/01/25 23:10:30 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -20,6 +20,9 @@
 /*
  * prototypes for prepjointree.c
  */
+extern int	from_collapse_limit;
+extern int	join_collapse_limit;
+
 extern Node *pull_up_IN_clauses(Query *parse, Node *node);
 extern Node *pull_up_subqueries(Query *parse, Node *jtnode,
 				   bool below_outer_join);