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Date: Wed, 17 Sep 2003 10:38:08 +0200
From: Christoph Haller <ch@rodos.fzk.de>
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Subject: Re: sub query
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> Hi I have this problem, when I try to run this query:
>
> SELECT MAX(d), host_position FROM (SELECT host_position,
> COUNT(host_position) as d FROM sss_host GROUP BY host_position) as e;
>
> am getting and ERROR: Attribute e.host_position must be GROUPed or
used in
> an aggregate function.
>
> Please to advice what could be the problem and how can I rewrite it to
work
> thanks in advance.
>
As the error message says: e.host_position must be GROUPed

so (supposing you want a one row result showing the maximum count)

SELECT MAX(e.d), e.host_position FROM (SELECT host_position,
COUNT(host_position) as d FROM sss_host GROUP BY host_position) as e
GROUP BY e.host_position ORDER BY 1 LIMIT 1;

should match your intentions.

Regards, Christoph