class UserCertification < ActiveRecord::Base attr_accessible :certification_id, :user_id validates_presence_of :certification_id, :user_id validates_uniqueness_of :certification_id, :scope => :user_id, :message => 'already exists for this user.' # Makes sure users don't get certified twice belongs_to :user belongs_to :certification def user_name if user.blank? return "n/a (user ##{user_id} missing)" else return self.user.name end end end