Re: compute_query_id and pg_stat_statements

On Mon, Apr 26, 2021 at 7:00 PM Bruce Momjian <bruce(at)momjian(dot)us> wrote:
>
> On Mon, Apr 26, 2021 at 12:56:13PM -0400, Tom Lane wrote:
> > Stephen Frost <sfrost(at)snowman(dot)net> writes:
> > > * Bruce Momjian (bruce(at)momjian(dot)us) wrote:
> > >> Techically, pg_stat_statements can turn on compute_query_id when it is
> > >> loaded, even if it is 'off' in postgresql.conf, right? And
> > >> pg_stat_statements would know if an alternate hash method is being used,
> > >> right?
> >
> > > +1 on this approach.
> >
> > That'd make it impossible to turn off or adjust afterwards, wouldn't it?
> > I'm afraid the confusion stemming from that would outweigh any simplicity.
> >
> > I would be in favor of logging a message at startup to the effect of
> > "this is misconfigured" (as per upthread discussion), although whether
> > people would see that is uncertain.
>
> I think a user-visible warning at CREATE EXNTENSION would help too.

It would help a bit, but actually logging it would probably help more.
Most people don't run the CREATE EXTENSION commands manually, it's all
done as part of either system install scripts or of application
migrations.

But that doesn't mean it wouldn't be useful to do it for those that
*do* run things manually, it just wouldn't be sufficient in itself.

--
Magnus Hagander
Me: https://www.hagander.net/
Work: https://www.redpill-linpro.com/