# 新竞赛参加关系表 class JoinInCompetition < ActiveRecord::Base attr_accessible :competition_id, :user_id belongs_to :user, :class_name => "User", :foreign_key => :user_id belongs_to :competition, :class_name => "Contest", :foreign_key => :competition_id validates :user_id, presence: true validates :competition_id, presence: true end