Adjust the definition of RestrictInfo's left_relids and right_relids

fields: now they are valid whenever the clause is a binary opclause,
not only when it is a potential join clause (there is a new boolean
field canjoin to signal the latter condition).  This lets us avoid
recomputing the relid sets over and over while examining indexes.
Still more work to do to make this as useful as it could be, because
there are places that could use the info but don't have access to the
RestrictInfo node.

2 files changed, 19 insertions, 11 deletions

diff --git a/src/backend/optimizer/util/clauses.c b/src/backend/optimizer/util/clauses.c
index d6f0bb3ad2e..35efa6bc630 100644
--- a/src/backend/optimizer/util/clauses.c
+++ b/src/backend/optimizer/util/clauses.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.157 2003/12/28 21:57:37 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.158 2003/12/30 23:53:15 tgl Exp $
  *
  * HISTORY
  *	  AUTHOR			DATE			MAJOR EVENT
@@ -812,6 +812,20 @@ is_pseudo_constant_clause(Node *clause)
 }
 
 /*
+ * is_pseudo_constant_clause_relids
+ *	  Same as above, except caller already has available the var membership
+ *	  of the clause; this lets us avoid the contain_var_clause() scan.
+ */
+bool
+is_pseudo_constant_clause_relids(Node *clause, Relids relids)
+{
+	if (bms_is_empty(relids) &&
+		!contain_volatile_functions(clause))
+		return true;
+	return false;
+}
+
+/*
  * pull_constant_clauses
  *		Scan through a list of qualifications and separate "constant" quals
  *		from those that are not.
diff --git a/src/backend/optimizer/util/restrictinfo.c b/src/backend/optimizer/util/restrictinfo.c
index 2ae122e92a9..f77966a2262 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 1.20 2003/11/29 19:51:51 pgsql Exp $
+ *	  $PostgreSQL: pgsql/src/backend/optimizer/util/restrictinfo.c,v 1.21 2003/12/30 23:53:15 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -227,15 +227,9 @@ join_clause_is_redundant(Query *root,
 
 		if (redundant)
 		{
-			/*
-			 * It looks redundant, now check for "var = const" case. If
-			 * left_relids/right_relids are set, then there are definitely
-			 * vars on both sides; else we must check the hard way.
-			 */
-			if (rinfo->left_relids)
-				return true;	/* var = var, so redundant */
-			if (contain_var_clause(get_leftop(rinfo->clause)) &&
-				contain_var_clause(get_rightop(rinfo->clause)))
+			/* It looks redundant, but check for "var = const" case */
+			if (!bms_is_empty(rinfo->left_relids) &&
+				!bms_is_empty(rinfo->right_relids))
 				return true;	/* var = var, so redundant */
 			/* else var = const, not redundant */
 		}