In my Hibernate 3.1 web application, I'm allowing the user to save to the database in one session while a background thread is reading data from the database in a different session. I'm using hibernate.current_session_context_class="thread" and GetCurrentSession() to manage my sessions, guaranteeing that each thread has its own session. In theory I thought that would work fine, but I'm encountering strange problems. The saving works, but right after it's done then the background thread tries to update the same objects that were just saved by the saving thread (as evidenced by duplicate HQL statements in the log), even though it never even touches those objects! I've also gotten some NonUniqueObjectException and StaleObjectExceptions that are probably related to that problem too. How can this be, and how can I fix it? It doesn't make any sense...

Any help would be much appreciated! I'm at my wit's end :(

Hi,

The first thing I'd do would be to display the session memory address to check if you're right thinking your threads are sharing the same session.

If so, then you will certainly have to recheck your conf to see why two different threads get the same session.

It looks like both sessions have different memory addresses, so that's not the problem.

Any other ideas?

You're not using second level cache ? What is doing your background thread exactly ? How long do you keep your session objects ?

No second-level caching is enabled. The background thread just calls GetCurrentSession, begins a transaction, runs some queries to get some data, commits the transaction, and ends. I don't explicitly manage my Session objects, I just call GetCurrentSession whenever I need one.

Well, I never got NonUniqueObjectException without running in the same session :-/. It was always due to the creation of objects with same id from the proxied objects.

Did you try and flush and clear your session before commiting, so as to be sure there's no more data in it.

When calling getCurrentSession() after doing a transaction, I suppose you get a new Session ? Maybe you should check it too?