Horton

Re: Missing docs for new enable_group_by_reordering GUC

Alexander Korotkov <aekorotkov@gmail.com>

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From: Alexander Korotkov <aekorotkov@gmail.com>
To: Pavel Borisov <pashkin.elfe@gmail.com>
Cc: Andrei Lepikhov <lepihov@gmail.com>, Bruce Momjian <bruce@momjian.us>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2024-06-19T19:35:49Z
Lists: pgsql-hackers

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Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Add doc entry for the new GUC paramenter enable_group_by_reordering

  2. Explore alternative orderings of group-by pathkeys during optimization.

On Wed, Jun 19, 2024 at 6:02 PM Pavel Borisov <pashkin.elfe@gmail.com> wrote:
> On Wed, 19 Jun 2024 at 05:27, Alexander Korotkov <aekorotkov@gmail.com> wrote:
>>
>> On Tue, Jun 18, 2024 at 4:14 PM Pavel Borisov <pashkin.elfe@gmail.com> wrote:
>> >> Controls if the query planner will produce a plan which will provide <literal>GROUP BY</literal> keys presorted in the order of keys of a child node of the plan, such as an index scan. When disabled, the query planner will produce a plan with <literal>GROUP BY</literal> keys only reordered to match
>> >> the <literal>ORDER BY</literal> clause, if any. When enabled, the planner will try to produce a more efficient plan. The default value is on.
>> > A correction of myself: presorted -> sorted, reordered ->sorted
>>
>> Thank you for your review.  I think all of this make sense.  Please,
>> check the revised patch attached.
>
> To me patch v3 looks good.

Ok, thank you. I'm going to push this if no objections.

------
Regards,
Alexander Korotkov
Supabase