Re: Need SQL help, I'm stuck.

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От Martijn van Oosterhout
Тема Re: Need SQL help, I'm stuck.
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Msg-id 20011211103359.B32177@svana.org
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Ответ на Need SQL help, I'm stuck.  (Chris Albertson <chrisalbertson90278@yahoo.com>)
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On Mon, Dec 10, 2001 at 01:42:54PM -0800, Chris Albertson wrote:
> Help. I seem to have a case of "brain lock" and can't figure out
> something that I should know is simple.
>
> Here is what I am trying to do.  Let's say I have a table called
> T1 with columns C1, C2, C3, C4.  It contains data as follows
>
>   a  1  abcd  dfg
>   a  2  cvfr  erg
>   a  3  derg  hbg
>   b  1  cccc  rth
>   c  1  rdvg  egt
>   c  2  derf  ett
>
> I want a SQL query that returns these rows
>
>   a  3  derg  hbg
>   b  1  cccc  rth
>   c  2  derf  ett
>

How about:

select distinct on (C1) C1, C2, C3, C4 from T1 order by C1, C2 desc;
--
Martijn van Oosterhout <kleptog@svana.org>
http://svana.org/kleptog/
> Terrorists can only take my life. Only my government can take my freedom.

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