From: Tom Lane <tgl@sss.pgh.pa.us>
To: Joost Kraaijeveld <J.Kraaijeveld@Askesis.nl>
Cc: pgsql-performance@postgresql.org
Subject: Re: Why the difference in plans ??
Date: Fri, 15 Sep 2006 10:08:35 -0400
Message-ID: <24190.1158329315@sss.pgh.pa.us> (raw)
In-Reply-To: <1158309566.30482.29.camel@panoramix>
References: <1158309566.30482.29.camel@panoramix>
"Joost Kraaijeveld" <J.Kraaijeveld@Askesis.nl> writes:
> Why the difference and can I influence the result so that the first
> query plan (which is the fastest) is actually used in both cases (I
> would expect that the limit would be done after the sort?)?
It likes the second plan because 6694025.41/353 < 41812.78. It would
probably be right, too, if the number of matching rows were indeed 353,
but it seems there are only 7. Try increasing your statistics target
and re-analyzing.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, J.Kraaijeveld@Askesis.nl
Subject: Re: Why the difference in plans ??
In-Reply-To: <24190.1158329315@sss.pgh.pa.us>
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