I have the following mapping:

ClassA map has:

- a bag of ClassB (lazy="true", cascade="all-delete-orphan", inverse="true")

ClassB map has:

- a many-to-one property of ClassC (lazy="proxy", cascade="none")

ClassC map has:

- a bag of ClassD (lazy="true", cascade="all-delete-orphan", inverse="true")

We have recently realized that sometimes when changing and saving an instance of ClassA, we also need to add an item to ClassC's collection of ClassD. Or sometimes we need to change a property of ClassD in an item already existing in that collection.

So I changed the many-to-one property of ClassC in the ClassB map to cascade="save-update". That should do it, right.? It does not. If I also change lazy="false" on that many-to-one property, then it works fine.

It seems like NHibernate is not detecting when a proxied class has changed so that it can cascade the updates. I'm sure I'm missing something simple. Ideas?

Since the relationship for the Class D collection on Class C is marked as inverse=true no changes to the collection will be persisted. You need to change the C property of the class D objects (although you haven't shown it in your example).

Only one end of a bidirectional association can be persisted and you've marked your collection as the non-persistent end. If you want the collection to be persistent you need to remove the inverse=true

Cascading is separate issue that many stumble over. It's worth re-reading the sections on cascading and the inverse attribute in the documentation.

Cheers,

Symon.

Symon,

Thanks for the reply. The ClassD collection must be inverse because the foreign key in the table from class D to class C is not nullable. However, that should not be a problem because here's how I add a ClassD item to the collection in ClassC:


This is a well worn pattern and works fine. When I save a ClassC directly, ClassD persists just fine. The place that things are breaking down I believe is the many-to-one association to ClassC from ClassB. It is not cascading save-updates because of the lazy proxy. As I mentioned, when I change ClassC to not lazy in the ClassB map, all is well.

Tim