class PostReply < ActiveRecord::Base belongs_to :post belongs_to :reply, class_name: 'Post' validates_uniqueness_of :reply_id, scope: :post_id end # == Schema Information # # Table name: post_replies # # post_id :integer # reply_id :integer # created_at :datetime not null # updated_at :datetime not null # # Indexes # # index_post_replies_on_post_id_and_reply_id (post_id,reply_id) UNIQUE #