Re: Postgresql and Top N Analysis?

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От Larry Rosenman
Тема Re: Postgresql and Top N Analysis?
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Msg-id 372780000.1052861767@lerlaptop.iadfw.net
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Ответ на Postgresql and Top N Analysis?  ("Katka a Daniel Dunajsky" <daniel_katka@hotmail.com>)
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--On Tuesday, May 13, 2003 15:32:57 -0600 Katka a Daniel Dunajsky 
<daniel_katka@hotmail.com> wrote:

> Hello all,
>
> Can anyone give me an hit how to do Top 'N' Analysis in postgresql (if it
> is possible)? I see that postgresql does not have an pseudocolumn rownum,
> therefore I can't use query like this:
>
> SELECT   *
> FROM     (SELECT DISTINCT session_type_id FROM user_sessions ORDER BY
> session_type_id) as dummy GROUP BY dummy;
>
> Thank you for your time.

look at the LIMIT parameter of SELECT, If I'm reading you right.





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Larry Rosenman                     http://www.lerctr.org/~ler
Phone: +1 972-414-9812                 E-Mail: ler@lerctr.org
US Mail: 1905 Steamboat Springs Drive, Garland, TX 75044-6749



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