Date: Mon, 08 Oct 2018 10:24:56 -0700
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Subject: Re: transction_timestamp() inside of procedures
To: pgsql-hackers@lists.postgresql.org,Tom Lane <tgl@sss.pgh.pa.us>,Peter
 Eisentraut <peter.eisentraut@2ndquadrant.com>
CC: PostgreSQL-development <pgsql-hackers@postgresql.org>,Alvaro Herrera
 <alvherre@2ndquadrant.com>,Bruce Momjian <bruce@momjian.us>,Michael Paquier
 <michael@paquier.xyz>
From: Andres Freund <andres@anarazel.de>
Message-ID: <E28DF5C1-E2EB-49D6-AC94-AC5FB99E58CF@anarazel.de>
Precedence: bulk

Hi,

On October 8, 2018 10:14:34 AM PDT, Tom Lane <tgl@sss=2Epgh=2Epa=2Eus> wro=
te:
>Peter Eisentraut <peter=2Eeisentraut@2ndquadrant=2Ecom> writes:
>> On 02/10/2018 16:58, Andres Freund wrote:
>>> It's a bit weird to make this decision based on these two timestamps
>>> differing=2E  For one, it only indirectly seems to be guaranteed that
>>> xactStartTimestamp is even set to anything here (to 0 by virtue of
>being
>>> a global var)=2E
>
>> Maybe but it seems to be the simplest way without doing major surgery
>to
>> all this code=2E
>
>This patch doesn't apply over 07ee62ce9=2E  Also, I like the
>timestamp-comparison approach even less than Andres does: I think it's
>probably outright broken, especially since it treats the equality case
>as license to advance xactStartTimestamp=2E
>
>Surely there is some way that we can directly test whether we're inside
>a
>procedure or not?  I think the logic should be basically
>
>    if (!IsParallelWorker())
>+   {
>+       if (!InsideProcedure())
>            xactStartTimestamp =3D stmtStartTimestamp;
>+       else
>+           xactStartTimestamp =3D GetCurrentTimestamp();
>+   }
>    else
>       Assert(xactStartTimestamp !=3D 0);

Seems more reasonable from here=2E

Andres
--=20
Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E