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From: Robert Haas <robertmhaas@gmail.com>
Date: Tue, 19 Apr 2022 07:39:57 -0400
Message-ID: <CA+TgmoaFp_C_A04FPqEOn4OL1TWbrRA0TPTDv7LL4HTbY0i+FQ@mail.gmail.com>
Subject: Re: TRAP: FailedAssertion("HaveRegisteredOrActiveSnapshot()", File:
 "toast_internals.c", Line: 670, PID: 19403)
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@anarazel.de>, Justin Pryzby <pryzby@telsasoft.com>, 
	Kyotaro Horiguchi <horikyota.ntt@gmail.com>, Erik Rijkers <er@xs4all.nl>, 
	Matthias van de Meent <boekewurm+postgres@gmail.com>, 
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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On Mon, Apr 18, 2022 at 4:07 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> There may be some corner cases that aren't described by any of these
> three blanket scenarios, but they've got to be pretty few and far
> between.

My first thought whenever anything like this comes up is cursors,
especially but not only holdable cursors. Also, plpgsql variables,
maybe mixed with embedded COMMIT/ROLLBACK. I don't find it
particularly hard to believe we have some bugs in
insufficiently-well-considered parts of the system that pass around
datums outside of the normal executor flow, but I don't know exactly
how to find them all, either.

-- 
Robert Haas
EDB: http://www.enterprisedb.com