Replace planner's representation of relation sets, per pghackers discussion.

Instead of Lists of integers, we now store variable-length bitmap sets.
This should be faster as well as less error-prone.

1 files changed, 20 insertions, 18 deletions

diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h
index 807c70073d..03240d6415 100644
--- a/src/include/nodes/relation.h
+++ b/src/include/nodes/relation.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: relation.h,v 1.78 2003/02/03 15:07:08 tgl Exp $
+ * $Id: relation.h,v 1.79 2003/02/08 20:20:55 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -15,16 +15,16 @@
 #define RELATION_H
 
 #include "access/sdir.h"
+#include "nodes/bitmapset.h"
 #include "nodes/parsenodes.h"
 
+
 /*
  * Relids
- *		List of relation identifiers (indexes into the rangetable).
- *
- *		Note: these are lists of integers, not Nodes.
+ *		Set of relation identifiers (indexes into the rangetable).
  */
 
-typedef List *Relids;
+typedef Bitmapset *Relids;
 
 /*
  * When looking for a "cheapest path", this enum specifies whether we want
@@ -83,7 +83,7 @@ typedef struct QualCost
  * Parts of this data structure are specific to various scan and join
  * mechanisms.	It didn't seem worth creating new node types for them.
  *
- *		relids - List of base-relation identifiers; it is a base relation
+ *		relids - Set of base-relation identifiers; it is a base relation
  *				if there is just one, a join relation if more than one
  *		rows - estimated number of tuples in the relation after restriction
  *			   clauses have been applied (ie, output rows of a plan for it)
@@ -104,6 +104,8 @@ typedef struct QualCost
  *
  * If the relation is a base relation it will have these fields set:
  *
+ *		relid - RTE index (this is redundant with the relids field, but
+ *				is provided for convenience of access)
  *		rtekind - distinguishes plain relation, subquery, or function RTE
  *		varlist - list of Vars for physical columns (only if table)
  *		indexlist - list of IndexOptInfo nodes for relation's indexes
@@ -128,12 +130,12 @@ typedef struct QualCost
  *		baserestrictcost - Estimated cost of evaluating the baserestrictinfo
  *					clauses at a single tuple (only used for base rels)
  *		outerjoinset - For a base rel: if the rel appears within the nullable
- *					side of an outer join, the list of all relids
- *					participating in the highest such outer join; else NIL.
+ *					side of an outer join, the set of all relids
+ *					participating in the highest such outer join; else NULL.
  *					Otherwise, unused.
  *		joininfo  - List of JoinInfo nodes, containing info about each join
  *					clause in which this relation participates
- *		index_outer_relids - only used for base rels; list of outer relids
+ *		index_outer_relids - only used for base rels; set of outer relids
  *					that participate in indexable joinclauses for this rel
  *		index_inner_paths - only used for base rels; list of InnerIndexscanInfo
  *					nodes showing best indexpaths for various subsets of
@@ -174,8 +176,7 @@ typedef struct RelOptInfo
 	RelOptKind	reloptkind;
 
 	/* all relations included in this RelOptInfo */
-	Relids		relids;			/* integer list of base relids (rangetable
-								 * indexes) */
+	Relids		relids;			/* set of base relids (rangetable indexes) */
 
 	/* size estimates generated by planner */
 	double		rows;			/* estimated number of result tuples */
@@ -190,6 +191,7 @@ typedef struct RelOptInfo
 	bool		pruneable;
 
 	/* information about a base rel (not set for join rels!) */
+	Index		relid;
 	RTEKind		rtekind;		/* RELATION, SUBQUERY, or FUNCTION */
 	List	   *varlist;
 	List	   *indexlist;
@@ -201,7 +203,7 @@ typedef struct RelOptInfo
 	List	   *baserestrictinfo;		/* RestrictInfo structures (if
 										 * base rel) */
 	QualCost	baserestrictcost;		/* cost of evaluating the above */
-	Relids		outerjoinset;	/* integer list of base relids */
+	Relids		outerjoinset;	/* set of base relids */
 	List	   *joininfo;		/* JoinInfo structures */
 
 	/* cached info about inner indexscan paths for relation: */
@@ -585,11 +587,11 @@ typedef struct RestrictInfo
 	/*
 	 * If the clause looks useful for joining --- that is, it is a binary
 	 * opclause with nonoverlapping sets of relids referenced in the left
-	 * and right sides --- then these two fields are set to lists of the
-	 * referenced relids.  Otherwise they are both NIL.
+	 * and right sides --- then these two fields are set to sets of the
+	 * referenced relids.  Otherwise they are both NULL.
 	 */
-	List	   *left_relids;	/* relids in left side of join clause */
-	List	   *right_relids;	/* relids in right side of join clause */
+	Relids		left_relids;	/* relids in left side of join clause */
+	Relids		right_relids;	/* relids in right side of join clause */
 
 	/* valid if clause is mergejoinable, else InvalidOid: */
 	Oid			mergejoinoperator;		/* copy of clause operator */
@@ -683,8 +685,8 @@ typedef struct InnerIndexscanInfo
 typedef struct InClauseInfo
 {
 	NodeTag		type;
-	List	   *lefthand;		/* base relids in lefthand expressions */
-	List	   *righthand;		/* base relids coming from the subselect */
+	Relids		lefthand;		/* base relids in lefthand expressions */
+	Relids		righthand;		/* base relids coming from the subselect */
 	List	   *sub_targetlist;	/* targetlist of original RHS subquery */
 	/*
 	 * Note: sub_targetlist is just a list of Vars or expressions;