Re: How to select rows that are the max for each subcategory?
От | Harald Armin Massa |
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Тема | Re: How to select rows that are the max for each subcategory? |
Дата | |
Msg-id | 7be3f35d0809251106w6dccd62fsd43ec4f53825fe4c@mail.gmail.com обсуждение исходный текст |
Ответ на | Re: How to select rows that are the max for each subcategory? ("Harald Armin Massa" <haraldarminmassa@gmail.com>) |
Список | pgsql-general |
uuuuuups, you need to specify the table in the select, so select t.x,t.y,t.z from t join (select x, max(y) as my from t group by x) t1 on (t.x=t1.x and t.y=t1.my) On Thu, Sep 25, 2008 at 20:05, Harald Armin Massa <haraldarminmassa@gmail.com> wrote: > select x,y,z > from > t join (select x, max(y) as my from t group by x) t1 on (t.x=t1.x and t.y=t1.my) > > best wishes > > Harald > > On Thu, Sep 25, 2008 at 20:01, Kynn Jones <kynnjo@gmail.com> wrote: >> Suppose I have a table T that has, among its columns, the fields X and Y, >> where Y is an integer, and multiple rows with the same value of X are >> possible. I want to select the rows corresponding to the greatest values of >> Y for each value of X. E.g. suppose that T is >> X Y Z >> a 1 eenie >> a 3 meenie >> a 2 miny >> b 4 moe >> b 0 catch >> ...the result of the desired query would be >> a 3 meenie >> b 4 moe >> TIA! >> Kynnjo >> >> >> > > > > -- > GHUM Harald Massa > persuadere et programmare > Harald Armin Massa > Spielberger Straße 49 > 70435 Stuttgart > 0173/9409607 > no fx, no carrier pigeon > - > EuroPython 2009 will take place in Birmingham - Stay tuned! > -- GHUM Harald Massa persuadere et programmare Harald Armin Massa Spielberger Straße 49 70435 Stuttgart 0173/9409607 no fx, no carrier pigeon - EuroPython 2009 will take place in Birmingham - Stay tuned!
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