Di seguito è riportata la query di cui hai bisogno e una soluzione funzionante Nota:ho modificato l'intervallo di tempo in 24 ore
;with SourceData(HourTime, Value, RowNum)
as
(
select
datepart(hh, UTCTime) HourTime,
Value,
row_number() over (partition by datepart(hh, UTCTime) order by UTCTime) RowNum
from foo
union
select
datepart(hh, UTCTime) - 1 HourTime,
Value,
5
from foo
where datepart(mi, UTCTime) = 0
)
select cast(A.HourTime as varchar) + ':00' UTCTime, sum(case when A.Value = B.Value then 1 else 0 end) ConstantValues
from SourceData A
inner join SourceData B on A.HourTime = B.HourTime and
(B.RowNum = (A.RowNum - 1))
group by cast(A.HourTime as varchar) + ':00'
