-- Table var to store the gaps
declare @T table
(
DeviceID varchar(10),
PrevPeriodEnd datetime,
NextPeriodStart datetime
)
-- Get the gaps
;with cte as
(
select *,
row_number() over(partition by DeviceID order by Timestamp) as rn
from data
)
insert into @T
select
C1.DeviceID,
C1.Timestamp as PrevPeriodEnd,
C2.Timestamp as NextPeriodStart
from cte as C1
inner join cte as C2
on C1.rn = C2.rn-1 and
C1.DeviceID = C2.DeviceID and
datediff(s, C1.Timestamp, C2.Timestamp) > 5
-- Build islands from gaps in @T
;with cte1 as
(
-- Add first and last timestamp to gaps
select DeviceID, PrevPeriodEnd, NextPeriodStart
from @T
union all
select DeviceID, max(TimeStamp) as PrevPeriodEnd, null as NextPeriodStart
from data
group by DeviceID
union all
select DeviceID, null as PrevPeriodEnd, min(TimeStamp) as PrevPeriodEnd
from data
group by DeviceID
),
cte2 as
(
select *,
row_number() over(partition by DeviceID order by PrevPeriodEnd) as rn
from cte1
)
select
C1.DeviceID,
C1.NextPeriodStart as PeriodStart,
C2.PrevPeriodEnd as PeriodEnd
from cte2 as C1
inner join cte2 as C2
on C1.DeviceID = C2.DeviceID and
C1.rn = C2.rn-1
order by C1.DeviceID, C1.NextPeriodStart