possible to do a group by on a time interval? (or some other way to do this)

seselect max(mytimestamp) as time, sum(mymetric) as bytes from metrictable
where mymetric > ( select max(mymetric) from metrictable) - (1/96)

"mytimestamp" is a timestamp data type.

I want to get a sum for every 15 minute interval in the table. I will add a where clause to limit how far back I want to go. The where clause I have there now is just an example.

tried group by, group by rollup, analytic with a window.

do i need the model clause? I have never used that. I really do think there is a way to do this in straight sql. Been working on it for a while....

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