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

On Tue, Jul 28, 2020 at 10:55:04AM +0200, Julien Rouhaud wrote:
> On Tue, Jul 28, 2020 at 10:07 AM torikoshia <torikoshia@oss.nttdata.com> wrote:
> >
> > Thanks for updating!
> > I tested the patch setting log_statement = 'all', but %Q in
> > log_line_prefix
> > was always 0 even when pg_stat_statements.queryid and
> > pg_stat_activity.queryid are not 0.
> >
> > Is this an intentional behavior?
> >
> >[...]
> 
> Thanks for the tests!  That's indeed an expected behavior (although I
> wasn't aware of it), which isn't documented in this patch (I'll fix
> it).  The reason for that is that log_statements is done right after
> parsing the query:
> 
>     /*
>      * Do basic parsing of the query or queries (this should be safe even if
>      * we are in aborted transaction state!)
>      */
>     parsetree_list = pg_parse_query(query_string);
> 
>     /* Log immediately if dictated by log_statement */
>     if (check_log_statement(parsetree_list))
>     {
>         ereport(LOG,
>                 (errmsg("statement: %s", query_string),
>                  errhidestmt(true),
>                  errdetail_execute(parsetree_list)));
>         was_logged = true;
>     }
> 
> As parse analysis is not yet done, no queryid can be computed at that
> point, so we always print 0.  That's a limitation that can't be
> removed without changing the semantics of log_statements, so we'll
> probably have to live with it.
> 
> > And here is a minor typo.
> >   optionnally -> optionally
> >
> >
> > > 753 +       /* query identifier, optionnally computed using
> > > post_parse_analyze_hook */
> 
> Thanks, I fixed it locally!


Recent conflict, rebased v11 attached.