From: Tom Lane <tgl@sss.pgh.pa.us>
To: Richard Frith-Macdonald <richard@tiptree.demon.co.uk>
Cc: pgsql-performance@postgresql.org
Subject: Re: Why is my (empty) partial index query slow?
Date: Thu, 22 Jun 2006 20:43:52 -0400
Message-ID: <9442.1151023432@sss.pgh.pa.us> (raw)
In-Reply-To: <BF749480-42C0-409D-B402-5A6EAA5592AC@tiptree.demon.co.uk>
References: <5510ED72-8266-438B-A4DF-9591ED26BA38@tiptree.demon.co.uk>
<511.1150992297@sss.pgh.pa.us>
<BF749480-42C0-409D-B402-5A6EAA5592AC@tiptree.demon.co.uk>
Richard Frith-Macdonald <richard@tiptree.demon.co.uk> writes:
> What has confused me is why a query using an empty index should be
> slow, irrespective of the state of the table that the index applies to.
Is it actually empty, or have you just deleted-and-not-yet-vacuumed
all the rows in the index?
I had hoped to see comparative EXPLAIN ANALYZE output for the fast and
slow cases. Maybe when it gets slow again you could redo the explain.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, richard@tiptree.demon.co.uk
Subject: Re: Why is my (empty) partial index query slow?
In-Reply-To: <9442.1151023432@sss.pgh.pa.us>
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