With CMR you can choose whether a Many relationship has a type of java.util.Set or java.util.Colledtion. In principle of Set is a collection which does not allow duplicates. However, when I add two objects in my set, both containing the same data, the engine does not complain. Is that normal behaviour?
I would expect not as even with a Collection I could never have a record twice when querying the database.
Joachim
