Re: Feature improvement: can we add queryId for pg_catalog.pg_stat_activity view?

On Tue, Oct  6, 2020 at 11:11:27AM +0800, Julien Rouhaud wrote:
> > I do think the queryid has to display independent of pg_stat_statements,
> > because I can see people using queryid for log file and pg_stat_activity
> > comparisons.  I also think the ability to have queryid accessible is an
> > important feature outside of pg_stat_statements, so I do think we need a
> > way to move this idea forward.
> 
> For the record, for now any extension can compute a queryid and there
> are at least 2 other published extensions that already do that, one of
> them having different semantics on how to compute the queryid.  I'm
> not sure that we'll ever get a consensus on those semantics due to
> performance tradeoff, so removing the ability to let people put their
> own code for that doesn't seem like the best way forward.
> 
> Maybe we could add a new hook for only queryid computation, and add a
> GUC to let people choose between no queryid computed, core computation
> (current pg_stat_statement) and 3rd party plugin?

That all seems very complicated.  If we go in that direction, I suggest
we just give up getting any of this into core.

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

  The usefulness of a cup is in its emptiness, Bruce Lee