Re: merge join killing performance

From: Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Matthew Wakeling <matthew(at)flymine(dot)org>, pgsql-performance(at)postgresql(dot)org
Subject: Re: merge join killing performance
Date: 2010-05-28 02:46:21
Message-ID: AANLkTinBVZmcknJjIQGr_suUnlOoBE8uxG-vGfiA7KWQ@mail.gmail.com
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On Thu, May 27, 2010 at 7:16 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com> writes:
>> So, Tom, so you think it's possible that the planner isn't noticing
>> all those nulls and thinks it'll just take a row or two to get to the
>> value it needs to join on?
>
> I've committed a patch for this, if you're interested in testing that
> it fixes your situation.

Cool, do we have a snapshot build somewhere or do I need to get all
the extra build bits like flex or yacc or bison or whatnot?

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