class AddCommonExtToLanguages < ActiveRecord::Migration def self.up # language.common_ext is a comma-separated list of common file # extensions. add_column :languages, :common_ext, :string # updating table information Language.reset_column_information common_ext = { 'c' => 'c', 'cpp' => 'cpp,cc', 'pas' => 'pas' } Language.find(:all).each do |lang| lang.common_ext = common_ext[lang.name] lang.save end end def self.down remove_column :languages, :common_ext end end