Calculated Column: TIme difference to next rowset

Hello Anonymous 

if you need a solution in Power Query then you can add a custom column with this formula. You have to replace the "PreviousStep" with the name of your previous step. Be aware that i use your index column for referencing the "next" step. Here the formula

try Duration.TotalMinutes(Table.SelectRows(PreviousStep, (sel)=> sel[Index] = [Index]+1)[timestamp]{0} - [timestamp]) otherwise null

here a complete code example to understand it better

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("rZLRagIxEEV/ZdjXik5msju6b7qmNWCzkGixyP7/b5jYbbUSIbA+JJCTmcnhkvO5YmSsZlVAhfC57nbWGbAB/NE56z7ijcT1e3GjvOAFISlQTUuYBc0y7t1JLwnS9L/DZh3MPk3rnRnrhlkSwZyI3e5TFd1ZjOjfi5IFzapQYTUqTM6CH7P4AYJlIrFuchaas0BUoYJ6VRbPRKhQhKZmIS1xFggXKvBrspCWKQtEF4roq0it04d+i6UKjPe9h3d7Ohy9AQXdd2zYGh+HzxlcfwBvvowPqV/d+V37woNNjVkgdaFeXQ3DBQ==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"rror num" = _t, #"error text" = _t, #"category num" = _t, #"category text" = _t, timestamp = _t, #"time no millis" = _t, Index = _t, #"short name" = _t, #"Line Name" = _t, IndexAll = _t]),
    PreviousStep = Table.TransformColumnTypes(Source,{{"rror num", Int64.Type}, {"error text", type text}, {"category num", Int64.Type}, {"category text", type text}, {"timestamp", type datetime}, {"time no millis", type datetime}, {"Index", Int64.Type}, {"short name", type text}, {"Line Name", type text}, {"IndexAll", Int64.Type}}),
    #"Added Custom" = Table.AddColumn(PreviousStep, "Custom", each try Duration.TotalMinutes(Table.SelectRows(PreviousStep, (sel)=> sel[Index] = [Index]+1)[timestamp]{0} - [timestamp]) otherwise null)
in
    #"Added Custom"

output

Copy paste this code to the advanced editor in a new blank query to see how the solution works.

If this post helps or solves your problem, please mark it as solution (to help other users find useful content and to acknowledge the work of users that helped you)
Kudoes are nice too

Have fun

Jimmy