Creating EJB 3.0 Entity Relationships - EJB 3.0 Database Persistence with Oracle Fusion Middleware 11g - page 251

After deleting some data, the Oracle Magazine catalog and the contained entities do
not get listed, but the other catalogs and the contained entities get listed.
Summary
In this chapter we discussed EJB 3.0 entity relationships between entity beans. We
mapped some database tables to entity beans. We added relationship mappings to
the entities. We added some test data and ran a test client to retrieve the entities and
the contained entities. We demonstrated the use of fetch strategy. In the next chapter
we shall create an Ajax user interface for EJB 3.0 entity bean persistence.