Can JPA/Hibernate be combined with other persistence framework like jOOQ?

You can map classes which have no 1:1 representation in the database, it's just more work in the mapping. If you want pure POJO s then use Hibernates xml mappings. Most complicated database schemas can be mapped and there are already a lot of questions on SO for them.

Post a question for each class and corresponding database tables/views/functions and we will find answers.

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