database - MySQL: Get all rows if specific value reached after date -


in mysql, want find rows value of column went 0 after specific date.

so, given data:

cat    value     date      95        2015-09-01      78        2015-10-01      0         2015-11-01      0         2015-12-01 b      129       2015-09-01 b      230       2015-10-01 b      201       2015-11-01 b      140       2015-12-01

in case, want run query asks:

which categories have 0 value after 10/1/2015 , had positive value before 11/1/2015?

the result should show category "a".

i suspect nested select statement, haven't quite figured out.

select * yourtable value = 0 , date > '2015-10-01' , cat in (   select distinct cat value > 0 , date < '2015-11-1' )

explanation: can split query 2 parts - inner query in statement in charge of getting cat id's positive before 11/1/15, , where value = 0 , date > '2015-10-01' give 0 after 10/1/15


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