Is it possible to have multiple inheritance strategies in an inheritance heirarchy? This is primarly for use with EJB3 POJOs. It does seem valuable to be able to have something like:



etc..

The reason for this is that the system I am designing will have a *lot* of polymorphism, and having it all in one table will be too much to manage. Each type may have a lot of new attributes as well and the sum will probably exceed the max number of columns if it is all in one table

Is this possible with hibernate (or should it be possible in a future version?)

or should I just take the perf hit for the joins? How bad is it really? I don't expect the inheritance heirarchy to go much deeper than ~10 levels but that is already quite deep if you have to join over 10 tables...

From what I can see it makes the sql visually more complicated, but it might speed things up significantly if I can choose where in the heirarchy to do the joins..

Thanks for any insight
Feint

Yes. Read the manual: http://www.hibernate.org/hib_docs/v3/re ... tance.html

Ok, I see how 9.1.4 somewhat addresses the question as well as some of 9.1.7..

Unfortunately I just finished digging into the EJB3 persistence spec draft 2 page 104:


Which means that even though Hibernate seems to support what I want to do, EJB does not..

ARGH..

Then just switch whole hog to hibernate. :)