benedmunds/CodeIgniter-Ion-Auth — pull request #388 by jrmadsen67 (2013-01-13 10:47:50+00:00)
Title: checks if user group record already exists & prevents duplicate

I could see moving this to a like named library function if you prefer, but duplicate users_groups records shouldn't be allowed

really, that table ought to just be a composite primary key & no id column, but that might break people's stuff... ?