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From: Amit Langote <amitlangote09@gmail.com>
Date: Wed, 24 Jun 2026 13:25:16 +0900
Message-ID: 
 <CA+HiwqEbqW_957S9UAEoZJ5aYyBF_Bp+ON+6thQNCySxSwv+Fg@mail.gmail.com>
Subject: Re: BUG #19484: Segmentation fault triggered by FDW
To: Richard Guo <guofenglinux@gmail.com>
Cc: Etsuro Fujita <etsuro.fujita@gmail.com>,
 Matheus Alcantara <matheusssilv97@gmail.com>,
	Ayush Tiwari <ayushtiwari.slg01@gmail.com>,
 Rafia Sabih <rafia.pghackers@gmail.com>,
	798604270@qq.com, pgsql-bugs@lists.postgresql.org,
	Amit Langote <amitlan@postgresql.org>
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Archived-At: 
 <https://www.postgresql.org/message-id/CA%2BHiwqEbqW_957S9UAEoZJ5aYyBF_Bp%2BON%2B6thQNCySxSwv%2BFg%40mail.gmail.com>
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On Wed, Jun 24, 2026 at 11:23=E2=80=AFAM Richard Guo <guofenglinux@gmail.co=
m> wrote:
> On Wed, Jun 24, 2026 at 10:43=E2=80=AFAM Amit Langote <amitlangote09@gmai=
l.com> wrote:
> > If we=E2=80=99d rather avoid it, I have a no-field alternative for REL_=
18: show_modifytable_info() is the only reader of the re-indexed list, and =
it can recompute the mapping from node->resultRelations and node->fdwPrivLi=
sts, both plan-ordered and untouched by pruning.
>
> This sounds like a nice solution.  Since show_modifytable_info() is
> only used for EXPLAIN, I guess the recompute overhead on the
> re-indexed list should be fine.

Thanks for chiming in, here is the patch to do so.

--
Thanks, Amit Langote

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