Hi,

I experimented a bit with hibernate and have some strange behaviour on rollback:

Transaction hibernateTransaction = hibernateSession.beginTransaction();

Employee employee = new Employee();
// initialize employee here

hibernateSession.save(employee);
hibernateTransaction.commit();

Iterator iter = hibernateSession.iterate("from " + Employee.class.getName()");
while ( iter.hasNext() ) {
System.out.println("found after commit" + iter.next());
}


hibernateSession.delete(employee);

//hibernateSession.flush();

hibernateTransaction.rollback();

iter = hibernateSession.iterate("from " + Employee.class.getName());
while ( iter.hasNext() ) {
System.out.println("found after rollback " + iter.next());
}


A employee is saved and commited. A delete is done, but rollbacked. However, the created employee is not found in the query. If I uncomment the flush, it works as expected.

I use hibernate 2.0.3

Armin

If I add a commit to the the end, the employee is deleted in the database also.

Armin

If you don't flush the session before the rollback(), the deleting is flushed to the database when you call iterate() - ie. in the next txn.

This is quite expected.

[quote="gavin"]If you don't flush the session before the rollback(), the deleting is flushed to the database when you call iterate() - ie. in the next txn.

This is quite expected.[/quote]

But what is with auto flush? My idea was, that set flush mode to auto flush exactly did the flush before commit and rolback automatically.

Armin

nope. autoflush flushes before commit, not before rollback

The test code slightly modified:

Transaction hibernateTransaction = hibernateSession.beginTransaction();

Employee employee = new Employee();
// initialize employee here

hibernateSession.save(employee);
hibernateTransaction.commit();

Iterator iter = hibernateSession.iterate("from " + Employee.class.getName()");
while ( iter.hasNext() ) {
System.out.println("found after commit" + iter.next());
}


hibernateSession.delete(employee);

//hibernateSession.flush();

hibernateTransaction.rollback();

iter = hibernateSession.iterate("from " + Employee.class.getName());
while ( iter.hasNext() ) {
System.out.println("found after rollback " + iter.next());
}

hibernateSession.flush();

hibernateTransaction.commit();

iter = hibernateSession.iterate("from " + Employee.class.getName());
while ( iter.hasNext() ) {
System.out.println("found after commit " + iter.next());
}



In words: save and commit a employee. Delete the employee, rolllback the transaction, flush and the commit!

The result is, that the employee is deleted in database and not found with the query!

My understanding for this code is that the saved employee should not be deleted. Is this understanding incorrect?


Armin

Yes your understanding is completely incorrect.

If you roll back a transaction, you should discard the Hibernate session.

[quote="gavin"]nope. autoflush flushes before commit, not before rollback[/quote]

Ok I found that in the documention, thanx, but I posted a slightly modified code example, I don't understand

Armin

[quote="gavin"]Yes your understanding is completely incorrect.

If you roll back a transaction, you should discard the Hibernate session.[/quote]

Ok, but then a problem occurs. I change the objects loaded from the now closed session and want to save them in a new session, I got an exception

net.sf.hibernate.HibernateException: Another object was associated with this id

Must I reload all the objects from the new session? But this breaks my long transaction semantics!

Armin