Database users and groups model -

i have 2 entities: users , groups. easiest model user(id,name,etc...), group(id,name), user_group_rel(user_id,group_id). need include groups other groups. 1 user can in many groups , groups can include users , subgroups own users , subgroups! need database model!

users , groups

while agree ken down's nomenclature, don't agree users , roles same entity.

base entities:

users     (user_id, user name, real name, user_status, etc) role      (role_id, role name, role_password, etc) privilege (priv_id, base object, functionality, have you) 

associative entities:

user has role (0 - n) (user_id, role_id) role has role (0 - n) (role_id, has_role_id) user has privilege (0 - n) (user_id, priv_id) role has privilege (0 - n) (role_id, priv_id)