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Ensure that mergejoin plan will be considered for FULL OUTER JOIN even

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if enable_mergejoin = OFF.  Must do this, because we have no other
implementation method for full joins.
This commit is contained in:
Tom Lane
2000-11-23 03:57:31 +00:00
parent 5479c11bfa
commit 48437f5c3a
2 changed files with 13 additions and 6 deletions
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9
src/backend/optimizer/path/joinpath.c
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@ -8,7 +8,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/path/joinpath.c,v 1.58 2000/10/05 19:48:26 momjian Exp $ * $Header: /cvsroot/pgsql/src/backend/optimizer/path/joinpath.c,v 1.59 2000/11/23 03:57:31 tgl Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
@ -75,9 +75,12 @@ add_paths_to_joinrel(Query *root,
List *mergeclause_list = NIL; List *mergeclause_list = NIL;
/* /*
* Find potential mergejoin clauses. * Find potential mergejoin clauses. We can skip this if we are not
* interested in doing a mergejoin. However, mergejoin is currently
* our only way of implementing full outer joins, so override
* mergejoin disable if it's a full join.
*/ */
if (enable_mergejoin) if (enable_mergejoin || jointype == JOIN_FULL)
mergeclause_list = select_mergejoin_clauses(joinrel, mergeclause_list = select_mergejoin_clauses(joinrel,
outerrel, outerrel,
innerrel, innerrel,

10
src/backend/optimizer/plan/initsplan.c
View File

@ -8,7 +8,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/optimizer/plan/initsplan.c,v 1.52 2000/11/16 22:30:25 tgl Exp $ * $Header: /cvsroot/pgsql/src/backend/optimizer/plan/initsplan.c,v 1.53 2000/11/23 03:57:31 tgl Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
@ -454,9 +454,13 @@ distribute_qual_to_rels(Query *root, Node *clause,
* joining. * joining.
* *
* We don't bother setting the merge/hashjoin info if we're not * We don't bother setting the merge/hashjoin info if we're not
* going to need it. * going to need it. We do want to know about mergejoinable ops
* in any potential equijoin clause (see later in this routine),
* and we ignore enable_mergejoin if isouterjoin is true, because
* mergejoin is the only implementation we have for full and right
* outer joins.
*/ */
if (enable_mergejoin || can_be_equijoin) if (enable_mergejoin || isouterjoin || can_be_equijoin)
check_mergejoinable(restrictinfo); check_mergejoinable(restrictinfo);
if (enable_hashjoin) if (enable_hashjoin)
check_hashjoinable(restrictinfo); check_hashjoinable(restrictinfo);