From: Bruce Momjian <pgman@candle.pha.pa.us>
Message-Id: <200208281701.g7SH1aI20777@candle.pha.pa.us>
Subject: Re: UPDATE & LIMIT together?
In-Reply-To: <20020828160929.GL20155@emaze.net>
To: tp@emaze.net
Date: Wed, 28 Aug 2002 13:01:36 -0400 (EDT)
Cc: pgsql-sql@postgresql.org
MIME-Version: 1.0
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You have to use a subquery returning the tables primary key to the
UPDATE:

	UPDATE tab SET x=1
	WHERE (primkey, col) IN (
		SELECT primkey,col FROM tab 
		ORDER BY col 
		LIMIT 10)

---------------------------------------------------------------------------

tp wrote:
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> Hi
> 
> I want to SELECT at max. 10 rows and SET a variable for the
> select 10 rows with the same query.
> 
> Under mysql i can use:
> UPDATE table SET uniq_iq=12345 LIMIT 10
> SELECT * FROM table WHERE uniq_id=1234;
> 
> This is not supported by postgres.
> 
> Is there some easy solution that does not require locking?
> 
> 
> -tp
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