JPA Save do not return updated Object when the primary Id is not Auto Generated

[assemble-code]

JPA Save do not return updated Object when the primary Id is not Auto Generated

[quaff]

I don't think entityManager.persist(entity) will know that field is generated by database.

Even when I tried fetching the object after the save the object do not contain the value form the database.

You should call entityManager.detach(entity) or entityManager.refresh(entity) first.

[assemble-code]

1. I tried entityManager.detach(savedEntity) and it worked,

2. but one thing i am not able to wrap head around is that even if the save is transactional and entity is committed then the entity in entityManager is detached , then findBy.. should not return older data as it shows selecte query being fired so it should get the new value as per my current understanding .

3. if the save or any method that can modify the value of db is called, shouldn't data be fetched from the database rather than using the persistent cache, As Save might have caused some fields to modified as result of db trigger or auto generated column, etc.

Sorry if questions are naive @quaff

[quaff]

1. I tried entityManager.detach(savedEntity) and it worked,
2. but one thing i am not able to wrap head around is that even if the save is transactional and entity is committed then the entity in entityManager is detached , then findBy.. should not return older data as it shows selecte query being fired so it should get the new value as per my current understanding .
3. if the save or any method that can modify the value of db is called, shouldn't data be fetched from the database rather than using the persistent cache, As Save might have caused some fields to modified as result of db trigger or auto generated column, etc.

Sorry if questions are naive @quaff

If your findBy... and save are in the same transaction, it will try to load entity from persistent context not database, if they are not in the same transaction but second level cache is enabled, it will try to load entity from cache not database.

[mp911de]

Closing this one as the save method behaves as designed along with JPA attached entity semantics. Any specifics that concern database-generated activity, flushing are out of our control as we use EntityManager.persist(…) in the regular case.