SQL: Select a row only if that cell has the max value given the ID -


i realize title of question more difficult question itself.

basically have dataset one:

id  hour 01  1 01  2 01  3 02  1 02  2 03  1 03  2 03  3 03  4

the dataset refers people playing game. id is, of course, id of subject whilst 'hour' refers happened in hour of game. now, select rows refer last hour played player.

so that:

id  hour 01  3 02  2 03  4

any ideas?

simply use max()

select id, max(hour) max_hour   tablename group  id

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