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

Commitfdda78e

Browse files
committed
Fix possible usage of incorrect UPPERREL_SETOP RelOptInfo
03d40e4 allowed dummy UNION [ALL] children to be removed from the planby checking for is_dummy_rel(). That commit neglected to still accountfor the relids from the dummy rel so that the correct UPPERREL_SETOPRelOptInfo could be found and used for adding the Paths to.Not doing this could result in processing of subsequent UNIONs using thesame RelOptInfo as a previously processed UNION, which could result inadd_path() freeing old Paths that are needed by the previous UNION.The same fix was independently submitted (2 mins later) by Richard Guo.Reported-by: Alexander Lakhin <exclusion@gmail.com>Author: David Rowley <dgrowleyml@gmail.com>Discussion:https://postgr.es/m/bee34aec-659c-46f1-9ab7-7bbae0b7616c@gmail.com
1 parent0a3d27b commitfdda78e

File tree

2 files changed

+9
-5
lines changed

2 files changed

+9
-5
lines changed

‎src/backend/optimizer/prep/prepunion.c‎

Lines changed: 6 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -773,6 +773,12 @@ generate_union_paths(SetOperationStmt *op, PlannerInfo *root,
773773
RelOptInfo*rel=lfirst(lc);
774774
Path*ordered_path;
775775

776+
/*
777+
* Record the relids so that we can identify the correct
778+
* UPPERREL_SETOP RelOptInfo below.
779+
*/
780+
relids=bms_add_members(relids,rel->relids);
781+
776782
/* Skip any UNION children that are proven not to yield any rows */
777783
if (is_dummy_rel(rel))
778784
continue;
@@ -815,8 +821,6 @@ generate_union_paths(SetOperationStmt *op, PlannerInfo *root,
815821
partial_pathlist=lappend(partial_pathlist,
816822
linitial(rel->partial_pathlist));
817823
}
818-
819-
relids=bms_add_members(relids,rel->relids);
820824
}
821825

822826
/* Build result relation. */

‎src/test/regress/expected/union.out‎

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -1260,14 +1260,14 @@ SELECT four FROM tenk1 WHERE 1=2
12601260
UNION
12611261
SELECT ten FROM tenk1 WHERE 1=2
12621262
ORDER BY 1;
1263-
QUERY PLAN
1264-
--------------------------------------
1263+
QUERY PLAN
1264+
-----------------------------------------------------------------------------------------
12651265
Sort
12661266
Output: unnamed_subquery.two
12671267
Sort Key: unnamed_subquery.two
12681268
-> Result
12691269
Output: unnamed_subquery.two
1270-
Replaces: Aggregate
1270+
Replaces: Aggregate on unnamed_subquery, unnamed_subquery_1, unnamed_subquery_2
12711271
One-Time Filter: false
12721272
(7 rows)
12731273

0 commit comments

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