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Re: query planning different in plpgsql?

From: Michal J(dot) Kubski <michal(dot)kubski(at)cdt(dot)pl>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: query planning different in plpgsql?
Date: 2009-10-26 10:05:23
Message-ID: 0ddf8c22989a34dc924fef1897bdc8d7@localhost (view raw or flat)
Thread:
Lists: pgsql-performance

Hi,

On Fri, 23 Oct 2009 16:56:36 +0100, Grzegorz Jaśkiewicz
<gryzman(at)gmail(dot)com> wrote:
> On Fri, Oct 23, 2009 at 4:49 PM, Scott Mead
> <scott(dot)lists(at)enterprisedb(dot)com>wrote:
> 
>>
>>
>>   Do you not have an index on last_snapshot.domain_id?
>>
> 
> that, and also try rewriting a query as JOIN. There might be difference
in
> performance/plan.
> 
Thanks, it runs better (average 240s, not 700s) with the index. Rewriting
queries
as JOINs does not make any difference.
The last_snapshot is a temp table created earlier in the procedure
and the query in question is preceded with CREATE TEMPORARY TABLE as well,
not a cursor. 
I still do not get why it performs differently inside the procedure. 
Is there any way to see what planning decisions were made?

Best regards,
Michal

-- 
I hear and I forget. I see and I believe. I do and I understand.
(Confucius)


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Subject: Re: query planning different in plpgsql?
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