From ba2ea6e0f5f270571e7f661cd2c7645160a9562a Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Tue, 19 Sep 2000 18:42:34 +0000
Subject: [PATCH] Fix GEQO optimizer to work correctly with new
outer-join-capable query representation. Note that GEQO_RELS setting is now
interpreted as the number of top-level items in the FROM list, not
necessarily the number of relations in the query. This seems appropriate
since we are only doing join-path searching over the top-level items.
---
src/backend/optimizer/geqo/geqo_eval.c | 50 +++++++++++++++-----------
src/backend/optimizer/geqo/geqo_main.c | 20 +++++------
src/backend/optimizer/geqo/geqo_pool.c | 14 ++++----
src/backend/optimizer/path/allpaths.c | 4 +--
src/include/optimizer/geqo.h | 12 ++++---
src/include/optimizer/geqo_pool.h | 5 +--
6 files changed, 57 insertions(+), 48 deletions(-)
diff --git a/src/backend/optimizer/geqo/geqo_eval.c b/src/backend/optimizer/geqo/geqo_eval.c
index f32b0d64eeb..1970ca9a43a 100644
--- a/src/backend/optimizer/geqo/geqo_eval.c
+++ b/src/backend/optimizer/geqo/geqo_eval.c
@@ -6,7 +6,7 @@
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: geqo_eval.c,v 1.54 2000/09/12 21:06:50 tgl Exp $
+ * $Id: geqo_eval.c,v 1.55 2000/09/19 18:42:33 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -36,7 +36,7 @@
* Returns cost of a query tree as an individual of the population.
*/
Cost
-geqo_eval(Query *root, Gene *tour, int num_gene)
+geqo_eval(Query *root, List *initial_rels, Gene *tour, int num_gene)
{
MemoryContext mycontext;
MemoryContext oldcxt;
@@ -64,7 +64,7 @@ geqo_eval(Query *root, Gene *tour, int num_gene)
savelist = root->join_rel_list;
/* construct the best path for the given combination of relations */
- joinrel = gimme_tree(root, tour, 0, num_gene, NULL);
+ joinrel = gimme_tree(root, initial_rels, tour, num_gene, 0, NULL);
/*
* compute fitness
@@ -86,35 +86,42 @@ geqo_eval(Query *root, Gene *tour, int num_gene)
/*
* gimme_tree
- * this program presumes that only LEFT-SIDED TREES are considered!
+ * this routine considers only LEFT-SIDED TREES!
*
- * 'old_rel' is the preceding join
+ * 'root' is the Query
+ * 'initial_rels' is the list of initial relations (FROM-list items)
+ * 'tour' is the proposed join order, of length 'num_gene'
+ * 'rel_count' is number of initial_rels items already joined (initially 0)
+ * 'old_rel' is the preceding join (initially NULL)
*
* Returns a new join relation incorporating all joins in a left-sided tree.
*/
RelOptInfo *
-gimme_tree(Query *root, Gene *tour, int rel_count, int num_gene,
- RelOptInfo *old_rel)
+gimme_tree(Query *root, List *initial_rels,
+ Gene *tour, int num_gene,
+ int rel_count, RelOptInfo *old_rel)
{
RelOptInfo *inner_rel; /* current relation */
- int base_rel_index;
+ int init_rel_index;
if (rel_count < num_gene)
- { /* tree not yet finished */
+ {
+ /* tree not yet finished */
+ init_rel_index = (int) tour[rel_count];
- /* tour[0] = 3; tour[1] = 1; tour[2] = 2 */
- base_rel_index = (int) tour[rel_count];
-
- inner_rel = (RelOptInfo *) nth(base_rel_index - 1, root->base_rel_list);
+ inner_rel = (RelOptInfo *) nth(init_rel_index - 1, initial_rels);
if (rel_count == 0)
- { /* processing first join with
- * base_rel_index = (int) tour[0] */
+ {
+ /* processing first join with init_rel_index = (int) tour[0] */
rel_count++;
- return gimme_tree(root, tour, rel_count, num_gene, inner_rel);
+ return gimme_tree(root, initial_rels,
+ tour, num_gene,
+ rel_count, inner_rel);
}
else
- { /* tree main part */
+ {
+ /* tree main part */
List *acceptable_rels = lcons(inner_rel, NIL);
List *new_rels;
RelOptInfo *new_rel;
@@ -133,13 +140,14 @@ gimme_tree(Query *root, Gene *tour, int rel_count, int num_gene,
}
new_rel = (RelOptInfo *) lfirst(new_rels);
- rel_count++;
- Assert(length(new_rel->relids) == rel_count);
-
/* Find and save the cheapest paths for this rel */
set_cheapest(new_rel);
- return gimme_tree(root, tour, rel_count, num_gene, new_rel);
+ /* and recurse... */
+ rel_count++;
+ return gimme_tree(root, initial_rels,
+ tour, num_gene,
+ rel_count, new_rel);
}
}
diff --git a/src/backend/optimizer/geqo/geqo_main.c b/src/backend/optimizer/geqo/geqo_main.c
index eb99c2478f8..755c33168d6 100644
--- a/src/backend/optimizer/geqo/geqo_main.c
+++ b/src/backend/optimizer/geqo/geqo_main.c
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: geqo_main.c,v 1.23 2000/08/07 00:51:23 tgl Exp $
+ * $Id: geqo_main.c,v 1.24 2000/09/19 18:42:33 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -65,13 +65,12 @@ static int gimme_number_generations(int pool_size, int effort);
*/
RelOptInfo *
-geqo(Query *root)
+geqo(Query *root, int number_of_rels, List *initial_rels)
{
int generation;
Chromosome *momma;
Chromosome *daddy;
Chromosome *kid;
- int number_of_rels;
Pool *pool;
int pool_size,
number_generations,
@@ -95,9 +94,6 @@ geqo(Query *root)
#endif
-/* set tour size */
- number_of_rels = length(root->base_rel_list);
-
/* set GA parameters */
pool_size = gimme_pool_size(number_of_rels);
number_generations = gimme_number_generations(pool_size, Geqo_effort);
@@ -114,7 +110,7 @@ geqo(Query *root)
pool = alloc_pool(pool_size, number_of_rels);
/* random initialization of the pool */
- random_init_pool(root, pool, 0, pool->size);
+ random_init_pool(root, initial_rels, pool, 0, pool->size);
/* sort the pool according to cheapest path as fitness */
sort_pool(pool); /* we have to do it only one time, since
@@ -204,7 +200,8 @@ geqo(Query *root)
/* EVALUATE FITNESS */
- kid->worth = geqo_eval(root, kid->string, pool->string_length);
+ kid->worth = geqo_eval(root, initial_rels,
+ kid->string, pool->string_length);
/* push the kid into the wilderness of life according to its worth */
spread_chromo(kid, pool);
@@ -247,9 +244,10 @@ geqo(Query *root)
best_tour = (Gene *) pool->data[0].string;
-/* root->join_relation_list_ will be modified during this ! */
- best_rel = (RelOptInfo *) gimme_tree(root, best_tour, 0,
- pool->string_length, NULL);
+/* root->join_rel_list will be modified during this ! */
+ best_rel = (RelOptInfo *) gimme_tree(root, initial_rels,
+ best_tour, pool->string_length,
+ 0, NULL);
/* DBG: show the query plan
print_plan(best_plan, root);
diff --git a/src/backend/optimizer/geqo/geqo_pool.c b/src/backend/optimizer/geqo/geqo_pool.c
index c8a970373ab..a149632dfa5 100644
--- a/src/backend/optimizer/geqo/geqo_pool.c
+++ b/src/backend/optimizer/geqo/geqo_pool.c
@@ -6,7 +6,7 @@
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: geqo_pool.c,v 1.17 2000/01/26 05:56:33 momjian Exp $
+ * $Id: geqo_pool.c,v 1.18 2000/09/19 18:42:33 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -84,18 +84,18 @@ free_pool(Pool *pool)
* initialize genetic pool
*/
void
-random_init_pool(Query *root, Pool *pool, int strt, int stp)
+random_init_pool(Query *root, List *initial_rels,
+ Pool *pool, int strt, int stp)
{
Chromosome *chromo = (Chromosome *) pool->data;
int i;
for (i = strt; i < stp; i++)
{
- init_tour(chromo[i].string, pool->string_length); /* from
- * "geqo_recombination.c"
- * */
-
- pool->data[i].worth = geqo_eval(root, chromo[i].string, pool->string_length); /* "from geqo_eval.c" */
+ init_tour(chromo[i].string, pool->string_length);
+ pool->data[i].worth = geqo_eval(root, initial_rels,
+ chromo[i].string,
+ pool->string_length);
}
}
diff --git a/src/backend/optimizer/path/allpaths.c b/src/backend/optimizer/path/allpaths.c
index 605b60b5845..be4a5ca56a2 100644
--- a/src/backend/optimizer/path/allpaths.c
+++ b/src/backend/optimizer/path/allpaths.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/optimizer/path/allpaths.c,v 1.63 2000/09/12 21:06:52 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/optimizer/path/allpaths.c,v 1.64 2000/09/19 18:42:34 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -188,7 +188,7 @@ make_one_rel_by_joins(Query *root, int levels_needed, List *initial_rels)
* rest will be skipped in case of GEQO *
*******************************************/
if (enable_geqo && levels_needed >= geqo_rels)
- return geqo(root);
+ return geqo(root, levels_needed, initial_rels);
/*
* We employ a simple "dynamic programming" algorithm: we first find
diff --git a/src/include/optimizer/geqo.h b/src/include/optimizer/geqo.h
index 1c6182f8d5f..e22d70badd9 100644
--- a/src/include/optimizer/geqo.h
+++ b/src/include/optimizer/geqo.h
@@ -6,7 +6,7 @@
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: geqo.h,v 1.20 2000/06/28 03:33:22 tgl Exp $
+ * $Id: geqo.h,v 1.21 2000/09/19 18:42:32 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -62,11 +62,13 @@ extern int Geqo_random_seed; /* or negative to use current time */
/* routines in geqo_main.c */
-extern RelOptInfo *geqo(Query *root);
+extern RelOptInfo *geqo(Query *root, int number_of_rels, List *initial_rels);
/* routines in geqo_eval.c */
-extern Cost geqo_eval(Query *root, Gene *tour, int num_gene);
-extern RelOptInfo *gimme_tree(Query *root, Gene *tour, int rel_count,
- int num_gene, RelOptInfo *old_rel);
+extern Cost geqo_eval(Query *root, List *initial_rels,
+ Gene *tour, int num_gene);
+extern RelOptInfo *gimme_tree(Query *root, List *initial_rels,
+ Gene *tour, int num_gene,
+ int rel_count, RelOptInfo *old_rel);
#endif /* GEQO_H */
diff --git a/src/include/optimizer/geqo_pool.h b/src/include/optimizer/geqo_pool.h
index f0791039fb7..d96e67139b1 100644
--- a/src/include/optimizer/geqo_pool.h
+++ b/src/include/optimizer/geqo_pool.h
@@ -6,7 +6,7 @@
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: geqo_pool.h,v 1.9 2000/01/26 05:58:20 momjian Exp $
+ * $Id: geqo_pool.h,v 1.10 2000/09/19 18:42:32 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -29,7 +29,8 @@
extern Pool *alloc_pool(int pool_size, int string_length);
extern void free_pool(Pool *pool);
-extern void random_init_pool(Query *root, Pool *pool, int strt, int stop);
+extern void random_init_pool(Query *root, List *initial_rels,
+ Pool *pool, int strt, int stop);
extern Chromosome *alloc_chromo(int string_length);
extern void free_chromo(Chromosome *chromo);
--
GitLab