Re: 7.3 LOCK TABLE problem - Mailing list pgsql-general

From Neil Conway
Subject Re: 7.3 LOCK TABLE problem
Date
Msg-id 1043699815.32114.182.camel@tokyo
Whole thread Raw
In response to Re: 7.3 LOCK TABLE problem  (Chris Gamache <cgg007@yahoo.com>)
Responses Re: 7.3 LOCK TABLE problem
List pgsql-general
On Mon, 2003-01-27 at 15:21, Chris Gamache wrote:
>     BEGIN;
>     LOCK TABLE queue IN EXCLUSIVE MODE;
>     UPDATE queue
>       set status=$$
>     WHERE id = (SELECT min(id)
>        FROM queue
>        WHERE status=0);

This is unrelated, but note that the sub-select would probably be faster
written as:

SELECT id FROM queue WHERE status = 0 ORDER BY id ASC LIMIT 1;

As this form of the query can use a btree index on "id" if one's
present.

>     SELECT id, data
>     FROM queue
>     WHERE status=$procid;

My Perl's a bit rusty, but AFAICS $procid is undefined. Perhaps 'perl
-w' and "use strict;" would be a good idea?

Cheers,

Neil

--
Neil Conway <neilc@samurai.com> || PGP Key ID: DB3C29FC




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