I am using Hibernate version 3 connecting to a Oracle database. I find out that when i execute the code below to update the object, though i see the SQL generated, it does not update the database, any help would be appreciated

Transaction transaction=session.beginTransaction();
transaction.begin();
session.saveOrUpdate(account);
transaction.commit();

I suggest you to enable P6spy logging (P6spy is free):
it shows you exactly what sql-statements (including commit/rollback statements) are executed against the db.

N.B.: Do you use JDBCTransactionFactory or JTA approach configuring a datasource?