From: Rajesh Kumar Mallah <mallah@trade-india.com>
Organization: Infocom Network Limited
To: <maggon@newgen.co.in>, <pgsql-sql@postgresql.org>
Subject: Re: IN Qeury Problem
Date: Thu, 17 Apr 2003 15:30:45 +0530
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Yes its a very well known problem and is
already there in the TODO. Its going to 
be fixed in 7.4 release the TODO says.

you can how every rewrite your query using 
EXISTS which is faster.


regds
mallah.

On Friday 18 Apr 2003 12:57 am, Sameer Maggon wrote:
> Hello,
>
>   I am facing a problem regarding the performance of postgres. I am
> concerned about the speed of the execution of a query when large number of
> entries is given in the IN clause.
>
> I have a Table with columns:
>
> FolderName (Indexed)
> FolderIndex (Indexed)
> ParentFolderIndex (Indexed)
> ...
> ..
>
> I have a query where i do a SELECT
>
> SELECT * FROM FolderTable WHERE PARENTFOLDERINDEX IN (38::int8, ......);
>
> If the number of values in IN clause is small, its working fine, but as and
> when the number of values increases the speed of the query is detoriating
> with a steep curve.
>
> How can this problem be solved ?
>
> Thanks and Regards
> Sameer Maggon
>
>
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-- 
Rajesh Kumar Mallah,
Project Manager (Development)
Infocom Network Limited, New Delhi
phone: +91(11)6152172 (221) (L) ,9811255597 (M)

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