Other Object database doesn't support JPA?
JPA is designed as an API for Object Relational Mapping (ORM), so many JPA features cannot be supported by regular object databases.
For example, user defined primary keys and composite primary keys are features of RDBMS (relational databases), which are not supported by most object databases. ObjectDB does support these features.
Some object databases support a subset of JPA but as far as we know currently no other object database supports JPA thoroughly as ObjectDB.
Thanks for ur help. Please clear my doubt
I know JPA is just a Specification and ORM Frameworks like Hibernate that implements JPA.we can compare JPA and JDO directly since both are specifications.
I want to know why JPA and Hibernate are compared directly? Is JPA is derived from Hibernate? If derived what is the reason behind it and what are advantages of JPA over Hibernate? Which ORM does Implements best of JPA?
Hibernate is an implementation of JPA.
It would be more appropriate to post additional questions on Hibernate to Hibernate forums.