# frozen_string_literal: true class IndexUserBadges < ActiveRecord::Migration[4.2] def change execute "DELETE FROM user_badges USING user_badges ub2 WHERE user_badges.badge_id = ub2.badge_id AND user_badges.user_id = ub2.user_id AND user_badges.post_id IS NOT NULL AND user_badges.id < ub2.id " add_index :user_badges, %i[badge_id user_id post_id], unique: true, where: "post_id IS NOT NULL" end end