I have the following tables:

       users (id, username, ... )
       roles (id, name)
 roles_users (user_id, role_id)

I am wondering how I can create a nice sort of user-role-grid from that which an admin can use to administer roles to users in a clear way. What I would like is basically a table full of checkboxes sort of like this:

        Login  Editor  Admin
Alice     ¦      ¦       ¦
Bob       ¦      ?       ?      
Carol     ¦      ¦       ?

                      [Apply]

Generating the table isn't too much of a deal, but I am very unsure how to handle it when it comes to how to name all the checkboxes and especially how to read and update the database in a not too clumsy way. Does anyone have any good advice or pointers on how to do this in a mostly clean way?

I'm using the Kohana 3 framework, if there is anything there that can make this even easier, but I of course welcome any answer.