Hi
I want to define some temporal filters so that I can retrieve the state of my data at a point in time. With a parent object and child collection objects, this seems to mean defining a many-to-many mapping (instead of one-to-many) to describe the relationship.
Then presumably I can create a new parent record every time the parent is updated or a new child record every time a child is updated and avoid data duplication whilst at the same retrieving only the subset of child records relevant at a particular point in time.
What I dont understand is how this would work with a table per subclass mapping (superclass data in Table A, subclass data in Table B). Would I now need to define a many-to-many mapping also between superclass and subclass - this seems wrong. Do I create a new record of B only when B is updated, or do I create both A and B to be consistent?
Will I need to abandon table per subclass? That seems quite limiting.
thanks, Baljeet.