Finding Data Gaps Using Window Functions

Santi143 Apologies for the delay while I was on vacation over the holidays. Yes, it's possible to do this for multiple sources. Here's an example where I've added the "EventSource" column and the query looks for gaps in each source individually even though the same event is coming from both sources:

let T =
datatable(EventTime:datetime, Event:string, EventSource:string)[
    datetime(2020-01-03 19:00), 'a', '1',
    datetime(2020-01-03 19:01), 'a', '1',
    datetime(2020-01-03 19:07), 'a', '1',
    datetime(2020-01-03 19:00), 'a', '2',
    datetime(2020-01-03 19:01), 'a', '2',
    datetime(2020-01-03 19:02), 'a', '2',
    datetime(2020-01-03 19:03), 'a', '2',
    datetime(2020-01-03 19:04), 'a', '2',
    datetime(2020-01-03 19:05), 'a', '2',
    datetime(2020-01-03 19:06), 'a', '2',
    datetime(2020-01-03 19:07), 'a', '2',
]
;
let newSessionLimit = 5m;
let dataFrequency = 1m;
T
| make-series count() on EventTime in range(datetime(2020-01-03 19:00), datetime(2020-01-03 19:10), dataFrequency) by EventSource
| mv-expand EventTime to typeof(datetime), count_
| where count_ != 0
| order by EventSource, EventTime asc
| extend prevTime = prev(EventTime), prevSource = prev(EventSource)
| where EventTime - prevTime > newSessionLimit and EventSource == prevSource
| project GapStart=prevTime+dataFrequency, GapEnd=EventTime, EventSource