Is it necessary to flush the session before committing a transaction?

Per the reference doc, it does not look like it...

Not needed - Hibernate will do it automatically. And although it doesn't harm to session.flush() before tx.commit(), I wouldn't recommend it for performance reason - flushing the session takes a time proprotional to the amount of elements loaded in the session...

Still, be aware that if your session flush mode is set to NEVER - tx.commit() will NOT flush it. In this mode, *you* are responsible to flush the session yourself...

Even though documentation does say that hibernate does flush out session persistent objects at regular intervals, I personally prefer to call flush() before every commit(). Just a habit from the JDBC days.

From the code:


So flush before commit is not needed ;)

(same kind of code for JTATransaction)