RubyGuide http://guides.rubyonrails.org/ Models Rails Database Migrations http://guides.rubyonrails.org/migrations.html This guide covers how you can use Active Record migrations to alter your database in a structured and organized manner. 日本語訳のページ http://wiki.usagee.co.jp/ruby/rails/RailsGuides%E3%82%92%E3%82%86%E3%81%A3%E3%81%8F%E3%82%8A%E5%92%8C%E8%A8%B3%E3%81%97%E3%81%A6%E3%81%BF%E3%81%9F%E3%82%88/Rails%20Database%20Migrations こちらを見ながらやります。