Whats the difference between JPA and JDO specifications?

Question

I have been using Hibernate ORM, which is an implementation of the JPA specification to manage relational data. I have also heard of the JDO specification that supposed to do the same (manage relational data).

What are the fundamental differences between the two? Any code samples most appreciated. How does JDO integrate with other Java technology stacks e.g. EJB3?

Answer 1

Try these JDO-JPA FAQ, JDO or JPA, JDO .v. JPA, JDO .v. JPA - API, JDO .v. JPA - ORM

JDO existed long before JPA, and has a wider scope. JPA is solely for RDBMS, and (even in JPA2) doesn't provide the full support that JDO provides. The links, and other posts in this forum should provide ample reading to explain all sides of the arguments.

--Andy (DataNucleus)