class CreateComments < ActiveRecord::Migration[4.2] def self.up create_table :comments, force: true do |t| t.column :title, :string, limit: 50, default: '' t.column :comment, :string, default: '' t.column :created_at, :datetime, null: false t.column :commentable_id, :integer, default: 0, null: false t.column :commentable_type, :string, limit: 15, default: '', null: false t.column :user_id, :integer, default: 0, null: false end add_index :comments, ['user_id'], name: 'fk_comments_user' end def self.down drop_table :comments end end