*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/optimizer/path/joinpath.c,v 1.41 1999/07/16 04:59:15 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/optimizer/path/joinpath.c,v 1.42 1999/07/27 06:23:12 tgl Exp $
*
*-------------------------------------------------------------------------
*/
/*
* best_innerjoin
* Find the cheapest index path that has already been identified by
- * (indexable_joinclauses) as being a possible inner path for the given
- * outer relation in a nestloop join.
+ * indexable_joinclauses() as being a possible inner path for the given
+ * outer relation(s) in a nestloop join.
*
- * 'join_paths' is a list of join nodes
- * 'outer_relid' is the relid of the outer join relation
+ * 'join_paths' is a list of potential inner indexscan join paths
+ * 'outer_relids' is the relid list of the outer join relation
*
- * Returns the pathnode of the selected path.
+ * Returns the pathnode of the best path, or NULL if there's no
+ * usable path.
*/
static Path *
best_innerjoin(List *join_paths, Relids outer_relids)
{
Path *path = (Path *) lfirst(join_path);
- if (intMember(lfirsti(path->joinid), outer_relids) &&
+ /* path->joinid is the set of base rels that must be part of
+ * outer_relids in order to use this inner path, because those
+ * rels are used in the index join quals of this inner path.
+ */
+ if (is_subset(path->joinid, outer_relids) &&
(cheapest == NULL ||
path_is_cheaper(path, cheapest)))
cheapest = path;
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/optimizer/path/joinrels.c,v 1.37 1999/07/16 04:59:15 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/optimizer/path/joinrels.c,v 1.38 1999/07/27 06:23:12 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "optimizer/tlist.h"
static List *new_joininfo_list(List *joininfo_list, Relids join_relids);
-static bool nonoverlap_sets(List *s1, List *s2);
-static bool is_subset(List *s1, List *s2);
static void set_joinrel_size(RelOptInfo *joinrel, RelOptInfo *outer_rel,
RelOptInfo *inner_rel, JoinInfo *jinfo);
static RelOptInfo *make_join_rel(RelOptInfo *outer_rel, RelOptInfo *inner_rel,
RelOptInfo *
get_cheapest_complete_rel(List *join_rel_list)
{
- List *xrel = NIL;
RelOptInfo *final_rel = NULL;
+ List *xrel;
/*
* find the relations that have no further joins, i.e., its joininfos
foreach(xrel, join_rel_list)
{
RelOptInfo *rel = (RelOptInfo *) lfirst(xrel);
- List *xjoininfo = NIL;
bool final = true;
+ List *xjoininfo;
foreach(xjoininfo, rel->joininfo)
{
return final_rel;
}
-static bool
-nonoverlap_sets(List *s1, List *s2)
-{
- List *x = NIL;
-
- foreach(x, s1)
- {
- int e = lfirsti(x);
-
- if (intMember(e, s2))
- return false;
- }
- return true;
-}
-
-static bool
-is_subset(List *s1, List *s2)
-{
- List *x = NIL;
-
- foreach(x, s1)
- {
- int e = lfirsti(x);
-
- if (!intMember(e, s2))
- return false;
- }
- return true;
-}
-
static void
set_joinrel_size(RelOptInfo *joinrel, RelOptInfo *outer_rel, RelOptInfo *inner_rel, JoinInfo *jinfo)
{
joinrel->tuples = ntuples;
}
+
+/*
+ * Subset-inclusion tests on integer lists.
+ *
+ * XXX these probably ought to be in nodes/list.c or some such place.
+ */
+
+bool
+nonoverlap_sets(List *s1, List *s2)
+{
+ List *x;
+
+ foreach(x, s1)
+ {
+ int e = lfirsti(x);
+
+ if (intMember(e, s2))
+ return false;
+ }
+ return true;
+}
+
+bool
+is_subset(List *s1, List *s2)
+{
+ List *x;
+
+ foreach(x, s1)
+ {
+ int e = lfirsti(x);
+
+ if (!intMember(e, s2))
+ return false;
+ }
+ return true;
+}
/*-------------------------------------------------------------------------
*
* paths.h
- * prototypes for various files in optimizer/paths (were separate
- * header files
+ * prototypes for various files in optimizer/path (were separate
+ * header files)
*
*
* Copyright (c) 1994, Regents of the University of California
*
- * $Id: paths.h,v 1.32 1999/07/27 03:51:01 tgl Exp $
+ * $Id: paths.h,v 1.33 1999/07/27 06:23:11 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "nodes/relation.h"
/*
- * allpaths.h
+ * allpaths.c
*/
extern RelOptInfo *make_one_rel(Query *root, List *rels);
/*
- * indxpath.h
+ * indxpath.c
* routines to generate index paths
*/
extern List *create_index_paths(Query *root, RelOptInfo *rel, List *indices,
extern List *expand_indexqual_conditions(List *indexquals);
/*
- * joinpath.h
+ * joinpath.c
* routines to create join paths
*/
extern void update_rels_pathlist_for_joins(Query *root, List *joinrels);
/*
- * orindxpath.h
+ * orindxpath.c
*/
extern List *create_or_index_paths(Query *root, RelOptInfo *rel, List *clauses);
/*
- * hashutils.h
+ * hashutils.c
* routines to deal with hash keys and clauses
*/
extern List *group_clauses_by_hashop(List *restrictinfo_list,
Relids inner_relids);
/*
- * joinutils.h
+ * joinutils.c
* generic join method key/clause routines
*/
extern bool order_joinkeys_by_pathkeys(List *pathkeys,
List *join_rel_tlist, List *joinclauses);
/*
- * mergeutils.h
+ * mergeutils.c
* routines to deal with merge keys and clauses
*/
extern List *group_clauses_by_order(List *restrictinfo_list,
List *mergeinfo_list);
/*
- * joinrels.h
+ * joinrels.c
* routines to determine which relations to join
*/
extern List *make_rels_by_joins(Query *root, List *old_rels);
extern List *make_rels_by_clauseless_joins(RelOptInfo *old_rel,
List *inner_rels);
extern RelOptInfo *get_cheapest_complete_rel(List *join_rel_list);
+extern bool nonoverlap_sets(List *s1, List *s2);
+extern bool is_subset(List *s1, List *s2);
/*
* prototypes for path/prune.c
projects / postgresql.git / commitdiff