Oracle store procedures for java programmers

hi experts

I have an interview next week  on oracle store procedures and i would like to know what are the oracle 11i store procedure concepts used in realtime programming with a java front end. I am a java programmer so i dont have  to know hard core store procudures . I just need to know what Oracle Store procuedure Concepts a java programmer should know which will help me in the interview.
I have experience with SQL statements like SELECT/INSERT/UPDATE/DELETE.
But I have  little knowledge of store procedures , a little knowledge of using
explicit ref cursors.
Can someone outline the other important concepts i need to know?
Like Merge command?

thanks in advance,
J