Andres Freund wrote:
> On Wednesday 23 December 2009 02:23:55 Jan Urbański wrote:
>> Lastly, I'm lacking good testcases
> If you want to see some queries which are rather hard to plan with random
> search you can look at
> http://archives.postgresql.org/message-
> id/200907091700.43411.and...@a
On Wednesday 23 December 2009 02:23:55 Jan Urbański wrote:
> Hi,
>
> I've been playing with using a Simulated Annealing-type algorithm for
> determinig join ordering for relations.
Very cool.
> Lastly, I'm lacking good testcases or even a testing approach: I'm
> generating silly queries and looki
Em 22-12-2009 22:23, Jan Urbański escreveu:
> o) the initial state is not really a random plan, it's usualy a
> left-deep tree (and is very inefficient) and this might skew results.
Maybe a QuickPick + SA.
http://www.springerlink.com/content/garn64gt61ju5xfa/
http://portal.acm.org/citation.cfm?do
=?UTF-8?B?SmFuIFVyYmHFhHNraQ==?= writes:
> I've been playing with using a Simulated Annealing-type algorithm for
> determinig join ordering for relations.
Cool.
> The code I have now creates the initial plan by doing something similar
> to what gimme_tree does in GEQO, but without any kind of he
I will follow it.
Thank you.
2009/12/23 Jan Urba��ski
> Hi,
>
> I've been playing with using a Simulated Annealing-type algorithm for
> determinig join ordering for relations. To get into context see
> http://archives.postgresql.org/pgsql-hackers/2009-05/msg00098.php
> (there's also a TODO in th
On Mon, Apr 13, 2009 at 7:17 PM, Tom Lane wrote:
> Robert Haas writes:
>> This isn't a very good plan. What we should do is first join the
>> values expression against bar, and then join the resulting rows
>> against foo. The optimizer doesn't want to do that, and I think the
>> reason is becau
Robert Haas writes:
> This isn't a very good plan. What we should do is first join the
> values expression against bar, and then join the resulting rows
> against foo. The optimizer doesn't want to do that, and I think the
> reason is because it knows that the left join might introduce null
> va
