All session info from cookie to database

[eluser]Grind[/eluser]
Sorry, I now see I mistyped my message.
I want a cookie, only with the session id. And I want a database with a session id and all the info CI stores in the database by default, along with the user id and the group id. Just it's then like so:

cookie
sesion_id

database
session_id
ip_address
user_agent
last_activity
user_data
user_id
group_id

The user_data in the database contains the userdata stored in the cookie, but I don't want it in the cookie: I just want a session id in the cookie. So I think that field isn't necessary.

Maybe this is a bit clearer (: