Simplify the planner's join clause management by storing join clauses

of a relation in a flat 'joininfo' list.  The former arrangement grouped
the join clauses according to the set of unjoined relids used in each;
however, profiling on test cases involving lots of joins proves that
that data structure is a net loss.  It takes more time to group the
join clauses together than is saved by avoiding duplicate tests later.
It doesn't help any that there are usually not more than one or two
clauses per group ...

1 files changed, 23 insertions, 9 deletions

diff --git a/src/backend/optimizer/util/restrictinfo.c b/src/backend/optimizer/util/restrictinfo.c
index 460ccc9546d..a76f1bb7a2e 100644
--- a/src/backend/optimizer/util/restrictinfo.c
+++ b/src/backend/optimizer/util/restrictinfo.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/util/restrictinfo.c,v 1.36 2005/06/05 22:32:56 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/util/restrictinfo.c,v 1.37 2005/06/09 04:19:00 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -24,7 +24,8 @@
 static RestrictInfo *make_restrictinfo_internal(Expr *clause,
 						   Expr *orclause,
 						   bool is_pushed_down,
-						   bool valid_everywhere);
+						   bool valid_everywhere,
+						   Relids required_relids);
 static Expr *make_sub_restrictinfos(Expr *clause,
 					   bool is_pushed_down,
 					   bool valid_everywhere);
@@ -40,14 +41,16 @@ static RestrictInfo *join_clause_is_redundant(PlannerInfo *root,
  * Build a RestrictInfo node containing the given subexpression.
  *
  * The is_pushed_down and valid_everywhere flags must be supplied by the
- * caller.
+ * caller.  required_relids can be NULL, in which case it defaults to the
+ * actual clause contents (i.e., clause_relids).
  *
  * We initialize fields that depend only on the given subexpression, leaving
  * others that depend on context (or may never be needed at all) to be filled
  * later.
  */
 RestrictInfo *
-make_restrictinfo(Expr *clause, bool is_pushed_down, bool valid_everywhere)
+make_restrictinfo(Expr *clause, bool is_pushed_down, bool valid_everywhere,
+				  Relids required_relids)
 {
 	/*
 	 * If it's an OR clause, build a modified copy with RestrictInfos
@@ -62,7 +65,8 @@ make_restrictinfo(Expr *clause, bool is_pushed_down, bool valid_everywhere)
 	Assert(!and_clause((Node *) clause));
 
 	return make_restrictinfo_internal(clause, NULL,
-									  is_pushed_down, valid_everywhere);
+									  is_pushed_down, valid_everywhere,
+									  required_relids);
 }
 
 /*
@@ -133,7 +137,8 @@ make_restrictinfo_from_bitmapqual(Path *bitmapqual,
 			list_make1(make_restrictinfo_internal(make_orclause(withoutris),
 												  make_orclause(withris),
 												  is_pushed_down,
-												  valid_everywhere));
+												  valid_everywhere,
+												  NULL));
 	}
 	else if (IsA(bitmapqual, IndexPath))
 	{
@@ -157,7 +162,8 @@ make_restrictinfo_from_bitmapqual(Path *bitmapqual,
  */
 static RestrictInfo *
 make_restrictinfo_internal(Expr *clause, Expr *orclause,
-						   bool is_pushed_down, bool valid_everywhere)
+						   bool is_pushed_down, bool valid_everywhere,
+						   Relids required_relids)
 {
 	RestrictInfo *restrictinfo = makeNode(RestrictInfo);
 
@@ -200,6 +206,12 @@ make_restrictinfo_internal(Expr *clause, Expr *orclause,
 		restrictinfo->clause_relids = pull_varnos((Node *) clause);
 	}
 
+	/* required_relids defaults to clause_relids */
+	if (required_relids != NULL)
+		restrictinfo->required_relids = required_relids;
+	else
+		restrictinfo->required_relids = restrictinfo->clause_relids;
+
 	/*
 	 * Fill in all the cacheable fields with "not yet set" markers. None
 	 * of these will be computed until/unless needed.  Note in particular
@@ -254,7 +266,8 @@ make_sub_restrictinfos(Expr *clause, bool is_pushed_down,
 		return (Expr *) make_restrictinfo_internal(clause,
 												   make_orclause(orlist),
 												   is_pushed_down,
-												   valid_everywhere);
+												   valid_everywhere,
+												   NULL);
 	}
 	else if (and_clause((Node *) clause))
 	{
@@ -272,7 +285,8 @@ make_sub_restrictinfos(Expr *clause, bool is_pushed_down,
 		return (Expr *) make_restrictinfo_internal(clause,
 												   NULL,
 												   is_pushed_down,
-												   valid_everywhere);
+												   valid_everywhere,
+												   NULL);
 }
 
 /*