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From: PetSerAl <petseral@gmail.com>
Date: Thu, 29 Jan 2026 22:04:25 +0300
Message-ID: <CAKygsHQutckTNjVaxhOKmP3x8C-dG6C-RiR8XapEo8Ozng1nhg@mail.gmail.com>
Subject: Re: About backups
To: Adrian Klaver <adrian.klaver@aklaver.com>
Cc: pgsql-general@lists.postgresql.org
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On Thu, Jan 29, 2026 at 9:37=E2=80=AFPM Adrian Klaver <adrian.klaver@aklave=
r.com> wrote:
> The window for this sort of thing isn't very large,

That window can be arbitrary large. It includes time waiting for locks
to be released from tables of interest.

--to reduce deadlocks take strongest lock first
--TRUNCATE requare ACCESS EXCLUSIVE
LOCK tablename;
--large amount of work
SELECT pg_sleep(10);
TRUNCATE tablename;

Now you have +10 seconds for the window for tablename and all
following tables in lock order.
IMHO, hidden data loss from TRUNCATE is much more sinister, than error
from ALTER TABLE.