That is a very good question and one that is not too easy to answer in very generic terms. Putting it very black and white, it would seem that for developers with a strong background in SQL – for example because of past Oracle Forms or PL/SQL programming experience, ADF BC gives a much easier learning curve and makes you much more productive than the more truly OO approach you can take with EJB 3.0, powered by for example Toplink.

When the application you are developing is very much data oriented, almost CRUD-like (Create/Retrieve/Update/Delete) – as is by the way the reasoning for many of the Ruby on Rails adepts – ADF BC will be easier and more productive, especially when you are leveraging the ADF Model (Data Binding) framework. It is exactly because of this reason that most of Oracle Fusion Applications will be built on the stack ADF BC (+ ADF Model) + ADF Faces.

When the application is not so much RDBMS oriented, possibly because there are multiple or at least different data sources to work against or because the application works against data services behind which a database may be lurking but which is not accessed directly or because there is a lot of middle tier business logic and relatively little DML activitiy, then a strong, sound OO domain model is probably the best way of working, and Toplink is the best option. Another consideration for using Toplink can be its advanced, shared cache: this allows for middle tier caching of (largely readonly) data that can help speed up performance and lower the load on the database. However, it is a complex business getting the best setup for high performance and scalability.

While a few years ago, a robust (and frequently complex) Object Relational Mapping was very much in vogue – to put it mildly – with a Domain Model (OO) created completely independently of the underlying database design and the ‘impedance mismatch’ overcome using fairly complex ORM frameworks, from EJB 2.1 to Hibernate and Toplink, it seems that these days a more pragmatic approach, accepting the database design as it is as the driving force for data operations, using simple Data Access technologies such as iBatis or even (Spring) JDBC or indeed ADF BC is much more done. And as I said, many advocates of the Ruby on Rails approach are ecstatic about this light weight approach to database access.

Of course this is only a very crude, short cut, off the cuff reaction. There are much more subtle considerations and factors in play. I am sure many others can add their 2 cts worth to this discussion.

regards

Lucas

Nice overviews and thoughts. In an Oracle shop as my company, what would you suggest between EJB 3.0 JPA with Toplink and Oracle ADF BC ? Do you have any recommendations for when and why to switch to one or another ?

Thanks,
Seb.

A version number like “11.0.4.0.2-112-patch2″ would be more like an actual Oracle version number