Compare multiple date/time columns and find the latest date

Hi lightw0rks ,

you can add a custom column with the following formula:

It allows you to add additional Date columns as well. It skips the first column of the table. 
But it could easily be changed to a solution where the date-columns are hardcoded if the dynamic solution is not desired.

This is the code to try out:

let
  Source = #table(
      {"ID", "Date1", "Date2", "Date3"}, 
      List.Zip(
          {
            {"1", "2", "3", "4"}, 
            {"01/07/2017 09:00", "01/07/2017 10:00", "01/07/2017 09:30", "01/07/2017 09:45"}, 
            {"10/09/2020 12:00", "null", "null", "03/08/2020 09:35"}, 
            {"12/03/2019 11:00", "null", "03/05/2020 09:00", "null"}
          }
        )
    ),
  #"Changed Type" = Table.TransformColumnTypes(
      Source, 
      {{"Date1", type datetime}, {"Date2", type datetime}, {"Date3", type datetime}}
    ),
  #"Added Custom" = Table.AddColumn(
      #"Changed Type", 
      "Custom", 
      each List.Max(List.Skip(Record.FieldValues(_)))
    )
in
  #"Added Custom"