Re: problem query ...

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От John Taylor
Тема Re: problem query ...
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Msg-id 02013117082906.01674@splash.hq.jtresponse.co.uk
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Ответ на problem query ...  (John Taylor <postgres@jtresponse.co.uk>)
Список pgsql-novice
On Thursday 31 January 2002 17:02, Tom Lane wrote:
> John Taylor <postgres@jtresponse.co.uk> writes:
> > I want to return 1 row for each id, that contains the maximum update
> > value for that id, and the values for name and desc.
>
> There's no simple way to do that in standard SQL.  However you can do
> it easily with SELECT DISTINCT ON, if you don't mind using a nonstandard
> construct.  See the "weather report" example on the SELECT reference
> page.

That was it!
I did try distinct on before, but was trying to be too complicated, with group or subselects.
What I wanted is:

select distinct on (id)  id,name,descr from john order by id,update desc;

Thanks
JohnT

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