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Repair bug in 8.2's new logic for planning outer joins: we have to allow joins

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that overlap an outer join's min_righthand but aren't fully contained in it,
to support joining within the RHS after having performed an outer join that
can commute with this one.  Aside from the direct fix in make_join_rel(),
fix has_join_restriction() and GEQO's desirable_join() to consider this
possibility.  Per report from Ian Harding.
This commit is contained in:
Tom Lane
2007-02-13 02:31:03 +00:00
parent 849b070707
commit c17117649b
4 changed files with 55 additions and 23 deletions
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22
src/backend/optimizer/geqo/geqo_eval.c
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@@ -6,7 +6,7 @@
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/backend/optimizer/geqo/geqo_eval.c,v 1.83 2007/01/05 22:19:30 momjian Exp $
* $PostgreSQL: pgsql/src/backend/optimizer/geqo/geqo_eval.c,v 1.84 2007/02/13 02:31:02 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -182,7 +182,7 @@ gimme_tree(Gene *tour, int num_gene, GeqoEvalData *evaldata)
* tour other than the one given. To the extent that the heuristics are
* helpful, however, this will be a better plan than the raw tour.
*
* Also, when a join attempt fails (because of IN-clause constraints), we
* Also, when a join attempt fails (because of OJ or IN constraints), we
* may be able to recover and produce a workable plan, where the old code
* just had to give up. This case acts the same as a false result from
* desirable_join().
@@ -262,9 +262,9 @@ desirable_join(PlannerInfo *root,
return true;
/*
* Join if the rels are members of the same outer-join side. This is
* needed to ensure that we can find a valid solution in a case where
* an OJ contains a clauseless join.
* Join if the rels overlap the same outer-join side and don't already
* implement the outer join. This is needed to ensure that we can find a
* valid solution in a case where an OJ contains a clauseless join.
*/
foreach(l, root->oj_info_list)
{
@@ -273,11 +273,15 @@ desirable_join(PlannerInfo *root,
/* ignore full joins --- other mechanisms preserve their ordering */
if (ojinfo->is_full_join)
continue;
if (bms_is_subset(outer_rel->relids, ojinfo->min_righthand) &&
bms_is_subset(inner_rel->relids, ojinfo->min_righthand))
if (bms_overlap(outer_rel->relids, ojinfo->min_righthand) &&
bms_overlap(inner_rel->relids, ojinfo->min_righthand) &&
!bms_overlap(outer_rel->relids, ojinfo->min_lefthand) &&
!bms_overlap(inner_rel->relids, ojinfo->min_lefthand))
return true;
if (bms_is_subset(outer_rel->relids, ojinfo->min_lefthand) &&
bms_is_subset(inner_rel->relids, ojinfo->min_lefthand))
if (bms_overlap(outer_rel->relids, ojinfo->min_lefthand) &&
bms_overlap(inner_rel->relids, ojinfo->min_lefthand) &&
!bms_overlap(outer_rel->relids, ojinfo->min_righthand) &&
!bms_overlap(inner_rel->relids, ojinfo->min_righthand))
return true;
}