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Re: Parallelize correlated subqueries that execute within each worker - Mailing list pgsql-hackers

From Zhihong Yu
Subject Re: Parallelize correlated subqueries that execute within each worker
Date
Msg-id CALNJ-vTpbZtTcJ+Y-kUc5D5_rNr4-1YY=-T2WF+t5425MSuCtQ@mail.gmail.com
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In response to Re: Parallelize correlated subqueries that execute within each worker  (James Coleman <jtc331@gmail.com>)
Responses Re: Parallelize correlated subqueries that execute within each worker
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On Tue, Sep 7, 2021 at 6:17 AM James Coleman <jtc331@gmail.com> wrote:
On Wed, Sep 1, 2021 at 7:06 AM Daniel Gustafsson <daniel@yesql.se> wrote:
>
> > On 7 May 2021, at 18:30, James Coleman <jtc331@gmail.com> wrote:
>
> > ..here we are now, and I finally have this patch cleaned up
> > enough to share.
>
> This patch no longer applies to HEAD, can you please submit a rebased version?

See attached.

Thanks,
James
Hi,
For v2-0002-Parallel-query-support-for-basic-correlated-subqu.patch :

+    * is when we're going to execute multiple partial parths in parallel

parths -> paths 

        if (index->amcanparallel &&
-           rel->consider_parallel && outer_relids == NULL &&
-           scantype != ST_BITMAPSCAN)
+               rel->consider_parallel && outer_relids == NULL &&
+               scantype != ST_BITMAPSCAN)

the change above seems unnecessary since the first line of if condition doesn't change.
Similar comment for the next hunk.

+            * It's not a partial path; it'a a full path that is executed as a subquery.

it'a a -> it's a

+           /* rel->consider_parallel_rechecking_params = false; */
+           /* rel->partial_pathlist = NIL; */

The commented code can be taken out.

Cheers

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