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To: "D'Arcy J.M. Cain" <darcy@druid.net>
Cc: pgsql-sql@postgresql.org
Subject: Re: SELECT FOR UPDATE locks whole table 
In-reply-to: <20021206190303.98BD31BA6@druid.net> 
References: <20021206190303.98BD31BA6@druid.net>
Comments: In-reply-to "D'Arcy J.M. Cain" <darcy@druid.net>
	message dated "Fri, 06 Dec 2002 14:03:02 -0500"
Date: Fri, 06 Dec 2002 18:00:24 -0500
Message-ID: <13898.1039215624@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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"D'Arcy J.M. Cain" <darcy@druid.net> writes:
> We have the following query:
> SELECT certificate_id
>     INTO TEMP TABLE x_certs
>     FROM certificate
>     WHERE cert_status = 0 AND
>         certificate_id BETWEEN 1111 AND 2222 AND
>         client_id IN (1, 2, 3)
>     ORDER BY certificate_id
>     FOR UPDATE;

> Is there any reason that this query should lock the entire certificate
> table?

It should only lock the selected rows ... and does, in a quick test
here.  Would you provide the test case that makes you think it's doing
otherwise?

			regards, tom lane