Hi everybody,

I have a test with two sessions, session1 and session2.

I have the simple following code (I minimize it so it will be much clear to read).

//Session1
session1 = HibernateUtil.openSession();
session1.beginTransaction();
Repository rpy = new Repository(key);
session1.saveOrUpdate(rpy);
session1.flush();

//Session2
session2 = HibernateUtil.openSession();
session2.beginTransaction();
Repository rpy = new Repository(key);
session2.saveOrUpdate(rpy);

//commit and close session1
session1.getTransaction().commit();
session1.close();

session2.flush(); //should fail on uniqueConstrains ...

Repository rpy = new Repository(key);
session2.saveOrUpdate(rpy);
session2.flush(); //should NOT fail on uniqueConstrains (row already in the database)...

//commit and close session2
session2.getTransaction().commit();
session2.close();



session2 invoke saveOrUpdate(object) before session1 commit and close it transaction.
So actually session2, make a select to see if it should insert, or update it's data.
In that case since session1 still not committed, session2 will make insert after it make flush() and get org.hibernate.exception.ConstraintViolationException.
Till now, everything is ok ... I want to check that in some test in our system.

But, after I commit with session1 and make the same operation with session2 (i.e saveOrUpdate(obj) and then flush()) I am expecting to get update operation on the object since it's already in the DB.

I am working with hibernate.

It works fine with Oracle DB, but not as expected with MySQL (i.e with Oracle I get only once ConstraintViolationException and it updating in the second time, but I am getting twice ConstraintViolationException when I am working infront of MySQL DB)

Do, someone, now the reason why and how can I solve it???

I tried to remove second-level-cache in hibernate configuration file, I tried to change the CacheMode of the session, unfortunately, nothing helped.

Can you please, advice?

Best regards,

Ofer Nagar