Difference between commit and flush in Hibernate

Commit will make the database commit
- Flushing is the process of synchronizing the underlying persistent
store with persistable state held in memory.
ie. it will update or insert into your tables in the running
transaction, but it _may_ not commit those changes (this depends on
your flush mode). When you have a persisted object and you change a
value on it, it becomes dirty and hibernate needs to flush these
changes to your persistence layer. It may do this automatically for
you or you may need to do this manually, that depends on your flush
mode, check http://www.hibernate.org/hib_docs/v3/api/org/hibernate/FlushMode.html
for further details on which flush mode is the right one for you.

http://www.coderanch.com/t/218534/ORM/databases/Difference-commit-flush-Hibernate