Re: WIP: Transportable Optimizer Mode - Mailing list pgsql-patches

From Simon Riggs
Subject Re: WIP: Transportable Optimizer Mode
Date
Msg-id 1218061922.4549.296.camel@ebony.2ndQuadrant
Whole thread Raw
In response to Re: WIP: Transportable Optimizer Mode  (Simon Riggs <simon@2ndquadrant.com>)
List pgsql-patches
On Sat, 2008-08-02 at 20:12 +0100, Simon Riggs wrote:
> Chris,
>
> Thanks for all of those changes... added as suggested (in next version)
>
> On Wed, 2008-07-30 at 14:58 -0400, chris wrote:
>
> > It's not clear to me that the plugin is actually working.
> >
> > When I run EXPLAIN against tables in "tomtestdb", I get results
> > consistent with an unanalyzed table.  So possibly the "hook" isn't
> > being used.  Perhaps I'm using it wrongly; perhaps what I have
> > documented above may suggest to you what's broken.
>
> The plugin works, but it currently extracts 0 for number of tuples. So
> you need to override that to give a different answer.
>
> I was going to add an SQL function to estimate the number of tuples in
> the same way as the optimizer does. That way we get the same answer from
> the EXPLAIN as we would have got on the main server and we don't need to
> run select count(*) against each table (unless we want to).

New version submitted together with stats hook patch on other thread.

--
 Simon Riggs           www.2ndQuadrant.com
 PostgreSQL Training, Services and Support


pgsql-patches by date:

Previous
From: Simon Riggs
Date:
Subject: Re: [HACKERS] get_relation_stats_hook()
Next
From: Simon Riggs
Date:
Subject: Re: [HACKERS] get_relation_stats_hook()