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Simplify the planner's join clause management by storing join clauses

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of a relation in a flat 'joininfo' list.  The former arrangement grouped
the join clauses according to the set of unjoined relids used in each;
however, profiling on test cases involving lots of joins proves that
that data structure is a net loss.  It takes more time to group the
join clauses together than is saved by avoiding duplicate tests later.
It doesn't help any that there are usually not more than one or two
clauses per group ...
This commit is contained in:
Tom Lane
2005-06-09 04:19:00 +00:00
parent c51815afed
commit a31ad27fc5
19 changed files with 285 additions and 465 deletions
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12
src/backend/optimizer/geqo/geqo_eval.c
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@@ -6,7 +6,7 @@
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/backend/optimizer/geqo/geqo_eval.c,v 1.75 2005/06/08 23:02:04 tgl Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/geqo/geqo_eval.c,v 1.76 2005/06/09 04:18:59 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -26,6 +26,7 @@
#include <math.h>
#include "optimizer/geqo.h"
#include "optimizer/joininfo.h"
#include "optimizer/pathnode.h"
#include "optimizer/paths.h"
#include "utils/memutils.h"
@@ -261,13 +262,8 @@ desirable_join(PlannerInfo *root,
/*
* Join if there is an applicable join clause.
*/
foreach(l, outer_rel->joininfo)
{
JoinInfo *joininfo = (JoinInfo *) lfirst(l);
if (bms_is_subset(joininfo->unjoined_relids, inner_rel->relids))
return true;
}
if (have_relevant_joinclause(outer_rel, inner_rel))
return true;
/*
* Join if the rels are members of the same IN sub-select. This is