user4853528 wrote:It is unlikely to be absolute.
I don't really know where to draw the line between what is business logic and what should be treated purely as a persistance concern.
What I'm not sure of is whether allocating and resolving ids should be the concern of the DAO layer or not.For starters you need to define the object data relationships.
At the moment, when the Bluray DAO is passed a Bluray object to store, it has to pull all the associated Person objects out of the Bluray and use the Person DAO to make sure records are created or update for those Person objects so that there are definitely Person record ids available to store in the Bluray record.No it doesn't. When you pull a disc you do not have to pull the actors. You might choose to do it but it is not required.