search for: assignments_users

I have a users table. I have a assignment table. and I have to log in to see my assignments. i can and I hasve a session id. I can make a new assignment and save my id in the user_id field of the assigment table. I want to share my assignments. so I can create a assignments_users table. this way I can have assignment 1 shared with user 1 and 2. and If I log in as user 1 or 2 I see the assignment. so assignement table has these fields for simplicity id name this is where I have problems thinking. how do get my session id to save into the assignments_users table with the id...