Does session.flush() commit the current transaction?

cowwoc · **Joined:** Tue Mar 02, 2004 6:17 pm **Posts:** 151

If I session.flush() in the middle of a transaction and transaction.rollback() later on, do my changes get undone all the way to the beginning of the transaction or only up to the last Session.flush()?

Thank you,
Gili

david · **Posted:** Mon Jun 06, 2005 9:02 pm

flush will execute any outstanding SQL operations only. No transaction state changes.

skewed · **Joined:** Tue Apr 19, 2005 4:32 pm **Posts:** 14

Quote:

flush will execute any outstanding SQL operations only. No transaction state changes.

I'm sorry, but the reply above is not very clear to me.

If I perform a session.flush() which causes SQL for an earlier session.save() to get executed. And then I explicitely rollback the transaction, will the SQL executed on flush also be rolled back?

In other words ..

Code:

Session s = sessionFactory.openSession();
Transaction tx = s.beginTransaction();
s.save(objA);
s.flush();
tx.rollback();
s.close();

Will 'objA' get saved to the database?

Also, if instead of rolling back the transaction, I simply close my session without committing, will the SQL executed on flush be rolled back?

Again ..

Code:

Session s = sessionFactory.openSession();
Transaction tx = s.beginTransaction();
s.save(objA);
s.flush();
s.close();  // close session without committing or rolling back

Will 'objA' get saved to the database?

Thanks, Rishabh

mchyzer · **Joined:** Sat Jul 17, 2004 5:16 pm **Posts:** 143

skewed wrote:

If I perform a session.flush() which causes SQL for an earlier session.save() to get executed. And then I explicitely rollback the transaction, will the SQL executed on flush also be rolled back?

It makes the SQL go across to the DB. So if your DB is setup so SQL will be rolled back (e.g. Oracle), then yes, all will be rolled back.

Quote:

Also, if instead of rolling back the transaction, I simply close my session without committing, will the SQL executed on flush be rolled back?

I dont know the defaults, but I could see if auto-commit mode was set to true on the connection (which is the default), then it could very well happen. Set that to false in the DB connection or in your pool, then probably it will not. You have all the sample code, so give it a try.

Chris

crisbroad · **Joined:** Mon Feb 11, 2013 3:46 am **Posts:** 1

session.flush()

just synchronizing with database (fetching latest data from DB), not updating DB with latest changes to POJO.

is this correct behaviour?

cris

Ajit Singh · **Joined:** Wed Feb 06, 2013 2:43 am **Posts:** 46

This is from the hibernate documents :
Except when you explicitly flush(), there are absolutely no guarantees about when the Session executes the JDBC calls, only the order in which they are executed.

However, Hibernate does guarantee that the Query.list(..) will never return stale or incorrect data.

So the thing is after the flush and before the commit, if you access DB directly then you will not see the changes from another session.

The flush is just synchronization with the db and then you need to commit or clear the session to see the changes.
And if you do just commit .It automatically flushes and you can see your changes from another session too.