Re: seq scan on indexed column

From: "Zhang, Anna" <azhang(at)verisign(dot)com>
To: "'postgresql(at)fruru(dot)com'" <postgresql(at)fruru(dot)com>
Cc: "'pgsql-admin(at)postgresql(dot)org'" <pgsql-admin(at)postgresql(dot)org>
Subject: Re: seq scan on indexed column
Date: 2002-03-14 23:09:30
Message-ID: 5511D658682A7740BA295CCF1E1233A635A873@vsvapostal2.bkup3
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Tycho,You saved us!
This problem really bothered us for a while, now we know why we had hard
time before. But I think it is a postgres bug. Thanks a lot!

Anna Zhang

-----Original Message-----
From: postgresql(at)fruru(dot)com [mailto:postgresql(at)fruru(dot)com]
Sent: Thursday, March 14, 2002 5:29 PM
To: Zhang, Anna
Cc: 'pgsql-admin(at)postgresql(dot)org'
Subject: Re: [ADMIN] seq scan on indexed column

On Thu, 14 Mar 2002, Zhang, Anna wrote:

> gtld_analysis=# explain SELECT NETBLOCK_START
> gtld_analysis-# FROM GTLD_OWNER
> gtld_analysis-# WHERE NETBLOCK_START = -2147483648;

You might want to try the same query but with the constant integer
enclosed in single quotes. I find that (at least for int8) this changes
the behaviour wrt index usage -- most probably due to automatic
typecasting in the postgresql SQL parser.

Hope this helps...
Tycho

--
Tycho Fruru tycho(dot)fruru(at)conostix(dot)com
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