From: Mike Rylander <mrylander@gmail.com>
To: akopciuch@bddf.ca
Cc: pgsql-sql@postgresql.org
Subject: Re: sql
Date: Mon, 25 Oct 2004 09:05:39 -0400
Message-ID: <b918cf3d04102506056ead8820@mail.gmail.com> (raw)
In-Reply-To: <200410250544.06403.akopciuch@bddf.ca>
References: <013901c4ba6a$8771d320$7202a8c0@aaa>
<b918cf3d041025042021ca123e@mail.gmail.com>
<200410250544.06403.akopciuch@bddf.ca>
On Mon, 25 Oct 2004 05:44:06 -0600, Andrew J. Kopciuch
<akopciuch@bddf.ca> wrote:
> 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 ...
Doh! Of course. Should have had coffee before writing that ;)
>
> 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: mrylander@gmail.com, akopciuch@bddf.ca
Subject: Re: sql
In-Reply-To: <b918cf3d04102506056ead8820@mail.gmail.com>
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