From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Tomas Vondra <tomas.vondra@2ndquadrant.com>,
        Nikhil Sontakke <nikhils@2ndquadrant.com>,
        David Steele <david@pgmasters.net>,
 Andres Freund <andres@anarazel.de>,
        Andrew Dunstan <andrew.dunstan@2ndquadrant.com>,
        Simon Riggs <simon@2ndquadrant.com>,
        Craig Ringer <craig@2ndquadrant.com>,
        Peter Eisentraut <peter.eisentraut@2ndquadrant.com>,
        Petr Jelinek <petr.jelinek@2ndquadrant.com>,
        Sokolov Yura <y.sokolov@postgrespro.ru>,
        Stas Kelvich <s.kelvich@postgrespro.ru>,
        Dmitry Dolgov <9erthalion6@gmail.com>,
        Masahiko Sawada <sawada.mshk@gmail.com>,
        PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: [HACKERS] logical decoding of two-phase transactions
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Mon, 16 Jul 2018 12:15:46 -0400"
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Date: Mon, 16 Jul 2018 13:21:17 -0400
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Robert Haas <robertmhaas@gmail.com> writes:
> I agree.  As a general statement, I think the idea of trying to
> prevent transactions from aborting is really scary.  It's almost an
> axiom of the system that we're always allowed to abort, and I think
> there could be a lot of unintended and difficult-to-fix consequences
> of undermining that guarantee.  I think it will be very difficult to
> create a sound system for delaying transactions, and I doubt very much
> that the proposed system is sound.

Ugh, is this patch really dependent on such a thing?

TBH, I think the odds of making that work are indistinguishable from zero;
and even if you managed to commit something that did work at the instant
you committed it, the odds that it would stay working in the face of later
system changes are exactly zero.  I would reject this idea out of hand.

			regards, tom lane