Re: *_collapse_limit, geqo_threshold

From: Andres Freund <andres(at)anarazel(dot)de>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: "Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov>, "Robert Haas" <robertmhaas(at)gmail(dot)com>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: *_collapse_limit, geqo_threshold
Date: 2009-07-07 16:10:02
Message-ID: 200907071810.02293.andres@anarazel.de
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Tuesday 07 July 2009 17:40:50 Tom Lane wrote:
> Andres Freund <andres(at)anarazel(dot)de> writes:
> > I cannot reasonably plan some queries with join_collapse_limit set to 20.
> > At least not without setting the geqo limit very low and a geqo_effort to
> > a low value.
> > So I would definitely not agree that removing j_c_l is a good idea.
> Can you show some specific examples? All of this discussion seems like
> speculation in a vacuum ...
I still may not publish the original schema (And I still have not heard any
reasonable reasons) - the crazy query in the referenced email shows similar
problems and has a somewhat similar structure.

If that is not enough I will try to design a schema that is similar and
different enough from the original schema. Will take a day or two though.

Andres

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Andrew Dunstan 2009-07-07 16:13:50 Re: Maintenance Policy?
Previous Message David E. Wheeler 2009-07-07 16:06:10 Re: Maintenance Policy?