org.hibernate.PersistentObjectException: detached entity passed to persist - ManyToMany Mapping

Question

• I have entity Patient and entity Test.
• Both have ManyToMany relationships each other.
• I added CASCADE_TYPE=ALL at both sides.
• I am using Hibernate EntityManager's persist(Patient); method.
• When i execute it it is throwing "org.hibernate.PersistentObjectException: detached entity passed to persist: Test"
• These are the screens.

The Patient class

The Test class

If anyone have solution please share it.

Thanks.

Answer 1

thanks. i changed it to em.merge() from em.persist(). works fine.

Answer 2

merge and persist do pretty different things with your entity. Are you really sure that merge accomplishes what you intended to do in the first place ? (see this topic over here )

Without seeing the code that you wrote to persist the test - entity, I can't really tell you what went wrong, but I could imagine it having something to do with the manyToMany-relationships that you have there. Are you sure you want to cascade.ALL ? If you remove a test -instance from the database, the cascade will remove every patient in that list. And then, for every patient in that list, it will cascade.REMOVE every test in the List<test> .

Answer 3

我建议尝试修改CASCADE_TYPE=PERSIST 。