From: Richard Ray <rray@mstc.state.ms.us>
To: pgsql-sql@postgresql.org
Subject: How to influence the planner
Date: Fri, 31 Aug 2007 13:32:17 -0500 (CDT)
Message-ID: <Pine.LNX.4.64.0708311116000.17749@rray.drdc.mstc.ms.gov> (raw)
I have a table, t1, with about 12 million rows
The column foo is unique and indexed
The column bar is not unique and is indexed
"select * from t1 where length(bar) = 0;" runs about 2 minutes
"select * from t1 where length(bar) = 0 order by foo ;" ran until I
stopped it after about 20 minutes
My simple solution is "select * into t2 from t1 where length(bar) = 0;"
and "select * from t2 order by foo ;"
Is there a way to make "select * from t1 where length(bar) = 0 order by foo ;"
or something similar work
Thanks
Richard Ray
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To: pgsql-sql@postgresql.org
Cc: rray@mstc.state.ms.us
Subject: Re: How to influence the planner
In-Reply-To: <Pine.LNX.4.64.0708311116000.17749@rray.drdc.mstc.ms.gov>
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