We are in the midst of restructuring our backend to utilize Hibernate and replace our current POJO structure (currently this is just a straight up call to various stored procedures). We have multiple RDBMS's to support and my main concern at the moment is determining the best method for handling generated ID's. Our main two platforms are SQL Server and DB2 (I know - odd), which both support IDENTITY, but shortly we'll be incoprorating Oracle which supports SEQUENCE only (oddly enough, DB2 supports both IDENTITY and SEQUENCE).

So, do we go native (which will require a certain amount of rewriting on our part, but that's inevitibale)? Create separate hbm.xml mappings per platform that target sequence or identity as appropriate (about 250 objects)? Is there another option I'm missing?

I'd love to hear from anyone who has implemented or has come to the same crossroads in decision making.

Thanks!

We are supporting PostgreSQL and MySQL in our application. PostgreSQL only has SEQUENCE generators and MySQL only has IDENTITY generator.
We are using the NATIVE generator in Hibernate and this works very well.

Thanks much for the replies - the new generators are definitely worth looking into.

Thanks much and wish me luck!