Re: nested queries vs. pg_stat_activity

Hi

po 10. 8. 2020 v 22:21 odesílatel Robert Haas <robertmhaas(at)gmail(dot)com>
napsal:

> On Mon, Aug 10, 2020 at 4:09 PM Magnus Hagander <magnus(at)hagander(dot)net>
> wrote:
> > Would it even solve the problem for them? pg_stat_statements collects
> aggregate stats and not a view of what's happening right now -- so it'd be
> mixing two different types of values. And it would get worse if the same
> thing is executed multiple times concurrently.
>
> True. You could find that you have a queryId that had already been
> evicted from the table.
>
> I think it's better to look for a more direct solution to this problem.
>

I am thinking about an extension (but it can be in core too) that does copy
query string and execution plan to shared memory to separate buffers per
session (before query start). It should eliminate a problem with
performance with locks

There can be two functions

show_query(pid int, "top" bool default true) .. it shows query without
truncating
show_plan(pid int, "top" bool default true, format text default "text")

When the argument "top" is false, then you can see the current query.

Regards

Pavel

> --
> Robert Haas
> EnterpriseDB: http://www.enterprisedb.com
> The Enterprise PostgreSQL Company
>
>
>