Re: sql group by statement

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От Jean-Luc Lachance
Тема Re: sql group by statement
Дата
Msg-id 3D8206A1.1B5B04FA@nsd.ca
обсуждение исходный текст
Ответ на sql group by statement  ("Albrecht Berger" <berger1517@gmx.ch>)
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How about:

select * from <Table> where (id, val2) in ( select id, max(val2) from
<Table> group by id);

JLL


Albrecht Berger wrote:
> 
> Hello,
> I have a problem, which I'm not able to solve with a simple query :
> 
> I need a resultset with distinct id's, but the max val2 of each id.
> I tried to group by id, but though I need the pk in my resultset
> I have to group it too, which "destroys" the group of val2.
> 
> Can this be done without a huge query ?
> 
> Table :
> pk   id   val1 val2
>  1    1    2   3
>  2    1    2   4
>  3    2    1   1
>  4    1    0   5
>  5    2    1   8
> 
> 
> Needed Result :
> pk   id   val1 val2
>  4    1    0   5
>  5    2    1   8
> 
> 
> Thx
> berger
> 
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