Re: compute_query_id and pg_stat_statements

Bruce Momjian <bruce@momjian.us>

From: Bruce Momjian <bruce@momjian.us>
To: Julien Rouhaud <rjuju123@gmail.com>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>, Pavel Stehule <pavel.stehule@gmail.com>, 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>, Stephen Frost <sfrost@snowman.net>, Christoph Berg <myon@debian.org>, Peter Eisentraut <peter.eisentraut@enterprisedb.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2021-05-14T12:35:14Z
Lists: pgsql-hackers
On Thu, May 13, 2021 at 09:41:42PM -0400, Bruce Momjian wrote:
> On Fri, May 14, 2021 at 09:40:15AM +0800, Julien Rouhaud wrote:
> > On Fri, May 14, 2021 at 8:13 AM Bruce Momjian <bruce@momjian.us> wrote:
> > >
> > > On Thu, May 13, 2021 at 08:04:37PM -0400, Álvaro Herrera wrote:
> > > > Here's a first attempt at what was suggested.  If you say "auto" it
> > > > remains auto in SHOW, but it gets enabled if a module asks for it.
> > > >
> > > > Not final yet, but I thought I'd throw it out for early commentary ...
> > >
> > > I certainly like this idea better than having the extension change the
> > > output of the GUC.
> > 
> > Oh, I didn't understand that it was the major blocker.  I'm fine with it too.
> 
> I think if we keep the output as 'auto', and document that you check
> pg_stat_activity for a hash to see if it is enabled, that gets us pretty
> far.

I think keeping the output as 'auto', and documenting that this query
must be run to determine if the query id is being computed:

	SELECT query_id
	FROM pg_stat_activity
	WHERE pid = pg_backend_pid();

is the right approach.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  If only the physical world exists, free will is an illusion.




Commits

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

  2. Move pg_stat_statements query jumbling to core.