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Make GEQO use dependent on table and index count.

This commit is contained in:
Bruce Momjian 1999-02-02 20:30:18 +00:00
parent eb3415538e
commit f1b7823471
4 changed files with 37 additions and 15 deletions
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7
doc/src/sgml/ref/set.sgml
View File

@ -406,7 +406,7 @@ SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL
</para>
<para>
This algorithm is on by default, which used GEQO for
statements of six or more tables.
statements of six or more tables and indexes.
(See the chapter on GEQO in the Programmer's Guide
for more information).
</para>
@ -676,6 +676,11 @@ SET TIME ZONE { '<REPLACEABLE CLASS="PARAMETER">timezone</REPLACEABLE>' | LOCAL
--
SET DATESTYLE TO 'ISO';
</programlisting>
<programlisting>
--Enable GEQO for queries with 4 or more tables and indexes
--
SET GEQO ON=4;
</programlisting>
<programlisting>
--Set GEQO to default:
--

25
src/backend/optimizer/path/allpaths.c
View File

@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/allpaths.c,v 1.23 1998/09/01 04:29:27 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/allpaths.c,v 1.24 1999/02/02 20:30:05 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -78,7 +78,6 @@ find_paths(Query *root, List *rels)
if (levels_needed <= 1)
{
/*
* Unsorted single relation, no more processing is required.
*/
@ -86,7 +85,6 @@ find_paths(Query *root, List *rels)
}
else
{
/*
* this means that joins or sorts are required. set selectivities
* of clauses that have not been set by an index.
@ -123,7 +121,7 @@ find_rel_paths(Query *root, List *rels)
rel_index_scan_list = find_index_paths(root,
rel,
find_relation_indices(root, rel),
find_relation_indices(root, rel),
rel->clauseinfo,
rel->joininfo);
@ -182,18 +180,27 @@ find_join_paths(Query *root, List *outer_rels, int levels_needed)
* genetic query optimizer entry point *
* <utesch@aut.tu-freiberg.de> *
*******************************************/
{
List *temp;
int paths_to_consider = 0;
if ((_use_geqo_) && length(root->base_rel_list) >= _use_geqo_rels_)
return lcons(geqo(root), NIL); /* returns *one* RelOptInfo, so
* lcons it */
foreach(temp, outer_rels)
{
RelOptInfo *rel = (RelOptInfo *) lfirst(temp);
paths_to_consider += length(rel->pathlist);
}
if ((_use_geqo_) && paths_to_consider >= _use_geqo_rels_)
/* returns _one_ RelOptInfo, so lcons it */
return lcons(geqo(root), NIL);
}
/*******************************************
* rest will be deprecated in case of GEQO *
*******************************************/
while (--levels_needed)
{
/*
* Determine all possible pairs of relations to be joined at this
* level. Determine paths for joining these relation pairs and
@ -207,7 +214,6 @@ find_join_paths(Query *root, List *outer_rels, int levels_needed)
prune_joinrels(new_rels);
#if 0
/*
* * for each expensive predicate in each path in each distinct
* rel, * consider doing pullup -- JMH
@ -247,7 +253,6 @@ find_join_paths(Query *root, List *outer_rels, int levels_needed)
if (BushyPlanFlag)
{
/*
* prune rels that have been completely incorporated into new
* join rels

14
src/backend/parser/gram.c
View File

@ -240,7 +240,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/parser/Attic/gram.c,v 2.66 1999/02/02 03:44:34 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/parser/Attic/gram.c,v 2.67 1999/02/02 20:30:07 momjian Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
@ -11450,11 +11450,17 @@ static Node *makeIndexable(char *opname, Node *lexpr, Node *rexpr)
least->val.val.str = match_least;
most->val.type = T_String;
most->val.val.str = match_most;
#ifdef USE_LOCALE
result = makeA_Expr(AND, NULL,
makeA_Expr(OP, "~", lexpr, rexpr),
makeA_Expr(OP, ">=", lexpr, (Node *)least));
#else
result = makeA_Expr(AND, NULL,
makeA_Expr(OP, "~", lexpr, rexpr),
makeA_Expr(AND, NULL,
makeA_Expr(OP, ">=", lexpr, (Node *)least),
makeA_Expr(OP, "<=", lexpr, (Node *)most)));
#endif
}
}
}
@ -11497,11 +11503,17 @@ static Node *makeIndexable(char *opname, Node *lexpr, Node *rexpr)
least->val.val.str = match_least;
most->val.type = T_String;
most->val.val.str = match_most;
#ifdef USE_LOCALE
result = makeA_Expr(AND, NULL,
makeA_Expr(OP, "~~", lexpr, rexpr),
makeA_Expr(OP, ">=", lexpr, (Node *)least));
#else
result = makeA_Expr(AND, NULL,
makeA_Expr(OP, "~~", lexpr, rexpr),
makeA_Expr(AND, NULL,
makeA_Expr(OP, ">=", lexpr, (Node *)least),
makeA_Expr(OP, "<=", lexpr, (Node *)most)));
#endif
}
}
}

6
src/man/set.l
View File

@ -1,6 +1,6 @@
.\" This is -*-nroff-*-
.\" XXX standard disclaimer belongs here....
.\" $Header: /cvsroot/pgsql/src/man/Attic/set.l,v 1.12 1999/02/02 03:45:33 momjian Exp $
.\" $Header: /cvsroot/pgsql/src/man/Attic/set.l,v 1.13 1999/02/02 20:30:18 momjian Exp $
.TH SET SQL 05/14/97 PostgreSQL PostgreSQL
.SH NAME
set - set run-time parameters for session
@ -44,7 +44,7 @@ determines the output format for the date and time data types.
.IR GEQO
enables or disables the genetic optimizer algorithm. This algorithm is
.IR on
by default, which used GEQO for statements of six or more tables.
by default, which used GEQO for statements of six or more tables and indexes.
Set the
.IR Programmer's Guide
for more information.
@ -101,7 +101,7 @@ set DateStyle to 'SQL,European'
.PP
.nf
--
--Use GEQO for statements with 4 or more tables
--Use GEQO for statements with 4 or more tables and indexes
--
set GEQO to 'on=4'
--