How to select rows that are the max for each subcategory?

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От Kynn Jones
Тема How to select rows that are the max for each subcategory?
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Msg-id c2350ba40809251101y81de3f8qb0e5daafeaad240f@mail.gmail.com
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Ответы Re: How to select rows that are the max for each subcategory?
Re: How to select rows that are the max for each subcategory?
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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



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