chatabase/db/migrate/20170430054633_create_messages.rb

class CreateMessages < ActiveRecord::Migration
  def change
    create_table :messages do |t|
      t.string     :nick   , :null => false
      t.string     :text   , :null => false
      t.belongs_to :client , :null => false , :index => true , :foreign_key => true

      t.timestamps :null => false
    end
  end
end