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From: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Date: Thu, 27 Mar 2025 17:55:24 +0530
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To: Etsuro Fujita <etsuro.fujita@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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On Tue, Mar 25, 2025 at 4:01=E2=80=AFPM Etsuro Fujita <etsuro.fujita@gmail.=
com> wrote:
>
> In the patch I also fixed a bug; I trusted XactReadOnly to see if the
> local transaction is READ ONLY, but I noticed that that is not 100%
> correct, because a transaction which started as READ WRITE can show as
> READ ONLY later within subtransactions, so I modified the patch so
> that postgres_fdw opens remote transactions in READ ONLY mode if the
> local transaction has been declared READ ONLY at the top level.

Nice catch. postgres_fdw replicates the transaction stack on foreign
server. I think we need to replicate it along with the transaction
properties. And also we need a test which tests readonly
subtransaction behaviour.

--=20
Best Wishes,
Ashutosh Bapat