I want to be able to do this:

Current user (u1) is member of 2 groups (g1,g2)

g1 users: u1, u3, u4, u5
g2 users: u1, u2, u5, u6

users info is stored in another table (users: username)

Now I want to be able to get the current users group friends printet out in a loop with there username but with no duplicates and without the current user... As you can see u5 is present in both groups...

Can this be done in a single query, and if yes... Please tell me how :-)