I am adjusting a Java program which writes incoming data into a table in a Firebird database. The database connection is abstracted by Hibernate. The command used to save the data is saveOrUpdate(). Some of these incoming data are new and need to be inserted, other exist already and need to be updated.

This works fine so far.
The problem I have occurs when removing rows from the database, e.g. by another thread. The next time data come in which existed already before the deletion Hibernate still tries to update and throws the exception


Is there a possibility to tell Hibernate the removal of entries so it does not try an update the next time but an insert?

The program does not open a new session each time but retrieves the current session when accessing the stored data:

You got that exception because Hibernate prevents losing updates.

One workaround would be to override @SQLUpdate and try to use the SQL MERGE clause which is supported by Firebase.

Thank you for your fast reply.
What are common solutions for removing data from the database so this problem cannot occur?
Searching the internet shows that the way I am doing it (using HQL) is basically fine.
Or is it necessary that one needs to override @SQLUpdate as soon as rows should be deleted?

You could delete an entity with bulk delete via HQL, but if a concurrent Session already loaded the deleting entity, you'd still get an OptimisticLockingException. That's actually desirable in most situations since it notifies you that you're using an old version of the current loading data.

In the previous response, I already mentioned two solutions to this situation.

Thank you