How do openfire's schema work?

Hi everyone .
I am learing for my thesis . I want load all user from LDAP to friendlist of other person , but i haven’t much idea . I think i will edit or modify database . And i want know openfire’s schema work with friendlist ???

What do table db storage friendlist ? And How to connect them in schema .
Thank a lot people verry verry much !
P/s : Do you have idea to automatic addfriend to friendlist ???