Hi, I'm a Newbie to EJB (as the email will make clearer). I want to Use CMP to do aggregate save to the Database for a hiearchy of objects. The hiearchy has 1 to many from parent to children objects. The hiearchy is 3 levels deep. How do i minimize the traffic to the DB. I did it thru a bmp / value objects set up but i really want to have the CMP do it for me. Also i want to do save of only dirty data. Any reference will be a great help.