sql - Group by statement to do average of time -

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my existing database has data coming id, value , time. there 1 record coming every 3 seconds. want select statement use these data , group them based on id , hrly basis show average of values in hr. how can use group by achieve ?

this sample data:

id  value   date       time   5       5/18/2015  10:27:22   9       5/18/2015  10:27:25 b   7       5/18/2015  10:27:22 b   8       5/18/2015  10:27:22

i have data coming in every 3 seconds. want aggregated based on every hr of day reflect avg values of id in hr. want output like

id -a , gives avg of 7 , @ 10 on 5/18/2015

this relatively simple group have 2 types of columns generally. grouped columns , aggregates. in case grouped columns have id,date, , hr(calculated [time]). have 1 aggregated column in case: average of value. check out code:

select id,        [date],        datepart(hour,[time]) hr,        avg(value)            avg_val yourtable group id,[date],datepart(hour,[time])

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