mysql - Excluding everything above denormalized date in query -


i denormalized data (so date split in year, month, day , hour column) wonder how query before date.

this not work:

select *   `impression_stat_hour`  doneforday =0 , (     year <=2011     , month <=6     , day <=30     , hour <=1 )

this won't "group" records want them too, resulting in date (for example) hour 0 , hour 1.

select ...     year < 2011     or (year = 2011 , month < 6)     or (year = 2011 , month = 6 , day < 30)     or (year = 2011 , month = 6 , day = 30 , hour <= 1)

or:

select ... str_to_date(concat(year,'-',month,'-',day,' ',hour,':00:00')) <= '2011-06-30 01:00:00';

the latter lot slower (since can't use indexes on various date columns. it's untested, since (ancient) version of mysql have access doesn't support str_to_date().


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