From: Tom Lane <tgl@sss.pgh.pa.us>
To: Richard Yen <dba@richyen.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: query plan with index having a btrim is different for strings of different length
Date: Wed, 10 Dec 2008 14:34:33 -0500
Message-ID: <6020.1228937673@sss.pgh.pa.us> (raw)
In-Reply-To: <E8AE9590-4E30-49C0-B11F-D7131009A095@richyen.com>
References: <751F49DC-1142-4E9C-95C8-BC3C229B3F0B@richyen.com>
<22937.1228865243@sss.pgh.pa.us>
<E8AE9590-4E30-49C0-B11F-D7131009A095@richyen.com>
Richard Yen <dba@richyen.com> writes:
> You guys are right. I tried "Miller" and gave me the same result. Is
> there any way to tune this so that for the common last names, the
> query run time doesn't jump from <1s to >300s?
If the planner's estimation is that far off then there must be something
very weird about the table statistics, but you haven't given us any clue
what.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, dba@richyen.com
Subject: Re: query plan with index having a btrim is different for strings of different length
In-Reply-To: <6020.1228937673@sss.pgh.pa.us>
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