From: Andrew J. Kopciuch <akopciuch@bddf.ca>
To: Mike Rylander <mrylander@gmail.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: sql
Date: Mon, 25 Oct 2004 05:44:06 -0600
Message-ID: <200410250544.06403.akopciuch@bddf.ca> (raw)
In-Reply-To: <b918cf3d041025042021ca123e@mail.gmail.com>
References: <013901c4ba6a$8771d320$7202a8c0@aaa>
<b918cf3d041025042021ca123e@mail.gmail.com>
On Monday 25 October 2004 05:20, Mike Rylander wrote:
> SELECT * FROM temp50 GROUP BY gc ORDER BY ora DESC;
You can not have have expressions (columns etc.) in the SELECT list that are
either not in a GROUP BY clause, or used in an aggregate function when you
use GROUP BY in the statement. By saying SELECT *, means you would have to
GROUP BY gc, co, data, ora ...
That isn't going to do what he wants. And the SQL you stated should give you
an error:
ERROR: column "temp50.co" must appear in the GROUP BY clause or be used in an
aggregate function
What he wants to do is use DISTINCT ON:
SELECT DISTINCT ON (gc) gc, co, data, ora FROM temp50 ORDER BY gc, ora DESC;
Andy
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To: pgsql-sql@postgresql.org
Cc: akopciuch@bddf.ca, mrylander@gmail.com
Subject: Re: sql
In-Reply-To: <200410250544.06403.akopciuch@bddf.ca>
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