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From: David Rowley <dgrowleyml@gmail.com>
Date: Mon, 31 Mar 2025 16:10:21 +1300
Message-ID: <CAApHDvp3EDrVhGjmb21bceJ5-Y7iXKOn2UGG3-ngp_9ob_mpLw@mail.gmail.com>
Subject: Re: Querying one partition in a function takes locks on all partitions
To: Renan Alves Fonseca <renanfonseca@gmail.com>
Cc: Evgeny Morozov <postgresql4@realityexists.net>, 
	pgsql-general <pgsql-general@postgresql.org>
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On Sat, 29 Mar 2025 at 10:30, Renan Alves Fonseca
<renanfonseca@gmail.com> wrote:
> Currently, in the SQL function path the plan is always generic. The
> planner ignores the function arguments. The plan_cache_mode setting
> has no effect in this path.
>
> I agree that the docs should be more explicit about this. There is a
> high penalty for using generic plans in complex functions.

If you have any suggestions about where you think those should be
added or wording for that, please feel free to suggest.

For the part that's specific to partitioning, I've suggested some
additional wording in the relevant spot in [1].

David

[1] https://postgr.es/m/CAApHDvogvzANoTOCyXUWgEuPFx1nT6S63aAN0bDRSJ=TaGBWew@mail.gmail.com