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

On Thu, Aug 1, 2019 at 11:05 PM Andres Freund <andres(at)anarazel(dot)de> wrote:
>
> I'm actually quite unconvinced that it's sensible to update the global
> value for nested queries. That'll mean e.g. the log_line_prefix and
> pg_stat_activity values are most of the time going to be bogus while
> nested, because the querystring that's associated with those will *not*
> be the value that the queryid corresponds to. elog.c uses
> debug_query_string to log the statement, which is only updated for
> top-level queries (outside of some exceptions like parallel workers for
> parallel queries in a function or stuff like that). And pg_stat_activity
> is also only updated for top level queries.

Having the nested queryid seems indeed quite broken for
log_line_prefix. However having the nested queryid in
pg_stat_activity would be convenient to track what is a long stored
functions currently doing. Maybe we could expose something like
top_level_queryid and current_queryid instead?