Re: distinct

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От bmccoy@chapelperilous.net
Тема Re: distinct
Дата
Msg-id Pine.LNX.4.10.10010092145010.4175-100000@chapelperilous.net
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Ответ на distinct  (andrew@networkcomputerz.com)
Список pgsql-general
On Tue, 3 Oct 2000 andrew@networkcomputerz.com wrote:

> I have attempted to run
> select distinct col1 from tablename;
> and it runs fine.
>
> When I run it in a real world environment: select distinct col1, col2,
> col3, col4 from tablename order by col1 desc, col2; It returns all the
> values from col1 which appears to be the same thing as not using
> distinct at all.

The DISTINCT constraint applies to all of the columns you are selecting,
not just the first one -- it selects all of the distinct TUPLES from the
query.

Brett W. McCoy
                                              http://www.chapelperilous.net
---------------------------------------------------------------------------
The Kennedy Constant:
    Don't get mad -- get even.



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