Security Filter Expression VS Slice

[Grant_Stead]

I have a table COMMIT,
I have a slice of commit with the following expression which works fine:
MAXROW(“COMMIT”, “commit_created_datetime”, [commit_REF_task]=[_THISROW].[commit_REF_task])=[_THISROW]

Why can’t this expression be on the security filter? (It say’s that a security filter can’t reference it’s own table.)

[Aleksi]

Without going deep, in generally it won’t work with the security filter because it’s possible that all the data is not in your table. With the slice you always have all the data and the expression can’t break it.