From: Tom Lane <tgl@sss.pgh.pa.us>
To: Pallav Kalva <pkalva@deg.cc>
Cc: pgsql-performance@postgresql.org
Subject: Re: Query Tuning
Date: Fri, 08 Oct 2004 12:42:56 -0400
Message-ID: <13657.1097253776@sss.pgh.pa.us> (raw)
In-Reply-To: <4166A8E8.4060102@deg.cc>
References: <4166A8E8.4060102@deg.cc>
Pallav Kalva <pkalva@deg.cc> writes:
> I have a problem with the below query, when i do explain on the
> below query on my live database it doesnt use any index specified on the
> tables and does seq scan on the table which is 400k records. But if i
> copy the same table onto a different database on a different machine it
> uses all the indexes specified and query runs much quicker.
It looks to me like you've never vacuumed/analyzed the copy, and so you
get a different plan there. The fact that that plan is better than the
one made with statistics is unhappy making :-( ... but when you only
show us EXPLAIN output rather than EXPLAIN ANALYZE, it's impossible to
speculate about why. Also, what PG version is this?
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, pkalva@deg.cc
Subject: Re: Query Tuning
In-Reply-To: <13657.1097253776@sss.pgh.pa.us>
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