Re: Updating a specific number of rows in pl/pgsql

>Assuming that there is a unique identifier on queue

Alas, there is not. The PK is made up of 4 columns.

--
Peter Headland
Architect
Actuate Corporation

-----Original Message-----
From: D'Arcy J.M. Cain [mailto:darcy@druid.net]
Sent: Tuesday, August 11, 2009 03:25
To: Peter Headland
Cc: pgsql-sql@postgresql.org
Subject: Re: [SQL] Updating a specific number of rows in pl/pgsql

On Mon, 10 Aug 2009 17:52:36 -0700
"Peter Headland" <pheadland@actuate.com> wrote:
> I can get the rows I want to update like this:
>
>   SELECT *
>    FROM queue
>    WHERE id = p_queue_id
>    ORDER BY rank
>    LIMIT p_number_of_items;
>
> Of course, there may not be p_number_of_items available in the queue.
>
> I want to update all the rows in the cursor in the same way:
>
>   UPDATE queue SET assigned = TRUE;

Assuming that there is a unique identifier on queue, let's call it
queue_id, you should be able to do something like this:
 UPDATE queue SET assigned = TRUE WHERE queue_id IN (SELECT queue_id   FROM queue   WHERE id = p_queue_id   ORDER BY
rank  LIMIT p_number_of_items); 

--
D'Arcy J.M. Cain <darcy@druid.net>         |  Democracy is three wolves
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