Re: Astonishing explain...! - Mailing list pgsql-general

From Neil Conway
Subject Re: Astonishing explain...!
Date
Msg-id 20020624194411.49896cf4.nconway@klamath.dyndns.org
Whole thread Raw
In response to Astonishing explain...!  (Mike Harding <mvh@ix.netcom.com>)
Responses Re: Astonishing explain...!  (Bruce Momjian <pgman@candle.pha.pa.us>)
List pgsql-general
On Mon, 24 Jun 2002 08:43:16 -0700 (PDT)
"Mike Harding" <mvh@ix.netcom.com> wrote:
> Why is a sequential scan be done for MAX of an indexed column?  This
> is obviously pretty painful for large tables...

This is an FAQ -- check the archives for much more discussion of it.
In short, the workaround is to create a btree index on the column
in question, and do:

SELECT num FROM boogers ORDER BY num LIMIT 1;

Cheers,

Neil

--
Neil Conway <neilconway@rogers.com>
PGP Key ID: DB3C29FC



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