Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit99e922a

Browse files
committed
Repair planner failure when there are multiple IN clauses, each with
a join in its subselect. In this situation we *must* build a bushyplan because there are no valid left-sided or right-sided join trees.Accordingly, hoary sanity check needs an update. Per report fromAlessandro Depase.
1 parent9dddd24 commit99e922a

File tree

2 files changed

+22
-3
lines changed

2 files changed

+22
-3
lines changed

‎src/backend/optimizer/path/allpaths.c

Lines changed: 3 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/optimizer/path/allpaths.c,v 1.109 2003/11/29 19:51:50 pgsql Exp $
11+
* $PostgreSQL: pgsql/src/backend/optimizer/path/allpaths.c,v 1.110 2003/12/17 17:07:48 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -545,6 +545,8 @@ make_one_rel_by_joins(Query *root, int levels_needed, List *initial_rels)
545545
/*
546546
* We should have a single rel at the final level.
547547
*/
548+
if (joinitems[levels_needed]==NIL)
549+
elog(ERROR,"failed to build any %d-way joins",levels_needed);
548550
Assert(length(joinitems[levels_needed])==1);
549551

550552
rel= (RelOptInfo*)lfirst(joinitems[levels_needed]);

‎src/backend/optimizer/path/joinrels.c

Lines changed: 19 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/optimizer/path/joinrels.c,v 1.64 2003/11/29 19:51:50 pgsql Exp $
11+
* $PostgreSQL: pgsql/src/backend/optimizer/path/joinrels.c,v 1.65 2003/12/17 17:07:48 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -226,7 +226,24 @@ make_rels_by_joins(Query *root, int level, List **joinrels)
226226
}
227227
}
228228

229-
if (result_rels==NIL)
229+
/*----------
230+
* When IN clauses are involved, there may be no legal way to make
231+
* an N-way join for some values of N. For example consider
232+
*
233+
* SELECT ... FROM t1 WHERE
234+
* x IN (SELECT ... FROM t2,t3 WHERE ...) AND
235+
* y IN (SELECT ... FROM t4,t5 WHERE ...)
236+
*
237+
* We will flatten this query to a 5-way join problem, but there are
238+
* no 4-way joins that make_join_rel() will consider legal. We have
239+
* to accept failure at level 4 and go on to discover a workable
240+
* bushy plan at level 5.
241+
*
242+
* However, if there are no IN clauses then make_join_rel() should
243+
* never fail, and so the following sanity check is useful.
244+
*----------
245+
*/
246+
if (result_rels==NIL&&root->in_info_list==NIL)
230247
elog(ERROR,"failed to build any %d-way joins",level);
231248
}
232249

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp