It should be nice (or should I say, the proper behaviour) when deleting a movie entry from EMMs database the corresponding actors/directors should also be automatically deleted (or with a confirmation dialog box or even better make the behaviour configurable in the options).
Of course this should only apply to actor entries where those actors are not part of another movie's details. In this way a user's database will only hold actor details for the present movies and a database will not hold unnecessary information following the deletion of a movie from the list.