database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-28 23:42:10 +03:00
Code Activity

Fix test for subplans in force-parallel mode.

Browse Source 
We mustn't force parallel mode if the query has any subplans, since
ExecSerializePlan doesn't transmit them to workers.  Testing
top_plan->initPlan is inadequate because (1) there might be initPlans
attached to lower plan nodes, and (2) non-initPlan subplans don't
work either.  There's certainly room for improvement in those
restrictions, but for the moment that's what we've got.

Amit Kapila, per report from Andreas Seltenreich

Discussion: <8737im6pmh.fsf@credativ.de>
This commit is contained in:
Tom Lane
2016-11-21 11:09:24 -05:00
parent c5f365f3ab
commit f24cf960d7
1 changed files with 2 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
src/backend/optimizer/plan/planner.c
View File

@ -342,11 +342,11 @@ standard_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
* actually a safe thing to do. (Note: we assume adding a Material node
* above did not change the parallel safety of the plan, so we can still
* rely on best_path->parallel_safe. However, that flag doesn't account
* for initPlans, which render the plan parallel-unsafe.)
* for subplans, which we are unable to transmit to workers presently.)
*/
if (force_parallel_mode != FORCE_PARALLEL_OFF &&
best_path->parallel_safe &&
top_plan->initPlan == NIL)
glob->subplans == NIL)
{
Gather *gather = makeNode(Gather);