Re: compute_query_id and pg_stat_statements

Julien Rouhaud <rjuju123@gmail.com>

From: Julien Rouhaud <rjuju123@gmail.com>
To: Pavel Stehule <pavel.stehule@gmail.com>
Cc: Kyotaro Horiguchi <horikyota.ntt@gmail.com>, Magnus Hagander <magnus@hagander.net>, Fujii Masao <masao.fujii@oss.nttdata.com>, Michael Paquier <michael@paquier.xyz>, Andres Freund <andres@anarazel.de>, Tom Lane <tgl@sss.pgh.pa.us>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Stephen Frost <sfrost@snowman.net>, Bruce Momjian <bruce@momjian.us>, Christoph Berg <myon@debian.org>, Peter Eisentraut <peter.eisentraut@enterprisedb.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2021-05-12T09:30:26Z
Lists: pgsql-hackers
On Wed, May 12, 2021 at 10:57:25AM +0200, Pavel Stehule wrote:
> 
> My second proposal can work for your example too. pg_stat_statements have
> to require any active queryid computing. And when it is not available, then
> the exception should be raised.
> 
> The custom queryid can return null, and still the queryid will be computed.
> Maybe the warning can be enough. Just, if somebody use pg_stat_statements
> function, then enforce the check if queryid is computed (compute_query_id
> is true || some hook is not null), and if not then raise a warning.

Ah I'm sorry I misunderstood your proposal.  Yes, definitely adding a warning
or an error when executing pg_stat_statements() SRF would help, that's a great
idea!

I'll wait a bit in case someone has any objection, and if not send an updated
patch!



Commits

  1. Allow compute_query_id to be set to 'auto' and make it default

  2. Move pg_stat_statements query jumbling to core.