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

Commitce1663c

Browse files
committed
Fix assertion failure when Parallel Append is run serially.
Parallel-aware plan nodes must be prepared to run without parallelismif it's not possible at execution time for whatever reason. Commitab72716, which introduced ParallelAppend, overlooked this.Rajkumar Raghuwanshi reported this problem, and I included his testcase in this patch. The code changes are by me.Discussion:http://postgr.es/m/CAKcux6=WqkUudLg1GLZZ7fc5ScWC1+Y9qD=pAHeqy32WoeJQvw@mail.gmail.com
1 parent4fa3964 commitce1663c

File tree

3 files changed

+31
-7
lines changed

3 files changed

+31
-7
lines changed

‎src/backend/executor/nodeAppend.c‎

Lines changed: 14 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -162,7 +162,7 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
162162
appendstate->as_whichplan=
163163
appendstate->ps.plan->parallel_aware ?INVALID_SUBPLAN_INDEX :0;
164164

165-
/*If parallel-aware, this will be overridden later. */
165+
/*For parallel query, this will be overridden later. */
166166
appendstate->choose_next_subplan=choose_next_subplan_locally;
167167

168168
returnappendstate;
@@ -361,14 +361,21 @@ choose_next_subplan_locally(AppendState *node)
361361
{
362362
intwhichplan=node->as_whichplan;
363363

364-
/* We should never see INVALID_SUBPLAN_INDEX in this case. */
365-
Assert(whichplan >=0&&whichplan <=node->as_nplans);
366-
367364
if (ScanDirectionIsForward(node->ps.state->es_direction))
368365
{
369-
if (whichplan >=node->as_nplans-1)
370-
return false;
371-
node->as_whichplan++;
366+
/*
367+
* We won't normally see INVALID_SUBPLAN_INDEX in this case, but we
368+
* might if a plan intended to be run in parallel ends up being run
369+
* serially.
370+
*/
371+
if (whichplan==INVALID_SUBPLAN_INDEX)
372+
node->as_whichplan=0;
373+
else
374+
{
375+
if (whichplan >=node->as_nplans-1)
376+
return false;
377+
node->as_whichplan++;
378+
}
372379
}
373380
else
374381
{

‎src/test/regress/expected/select_parallel.out‎

Lines changed: 11 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -121,6 +121,17 @@ select round(avg(aa)), sum(aa) from a_star a4;
121121
(1 row)
122122

123123
reset enable_parallel_append;
124+
-- Parallel Append that runs serially
125+
create or replace function foobar() returns setof text as
126+
$$ select 'foo'::varchar union all select 'bar'::varchar $$
127+
language sql stable;
128+
select foobar() order by 1;
129+
foobar
130+
--------
131+
bar
132+
foo
133+
(2 rows)
134+
124135
-- test with leader participation disabled
125136
set parallel_leader_participation = off;
126137
explain (costs off)

‎src/test/regress/sql/select_parallel.sql‎

Lines changed: 6 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -49,6 +49,12 @@ explain (costs off)
4949
select round(avg(aa)),sum(aa)from a_star a4;
5050
reset enable_parallel_append;
5151

52+
-- Parallel Append that runs serially
53+
create or replacefunctionfoobar() returns setoftextas
54+
$$select'foo'::varcharunion allselect'bar'::varchar $$
55+
language sql stable;
56+
select foobar()order by1;
57+
5258
-- test with leader participation disabled
5359
set parallel_leader_participation= off;
5460
explain (costs off)

0 commit comments

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