RailsのActive Recordeで、フィールドを変更する。

カラム（フィールド）の変更

$ rails g migration change_column_is_holiday_to_days
      invoke  active_record
      create    db/migrate/20160303132302_change_column_is_holiday_to_days.rb

$ rails g migration change_column_is_holiday_to_days

invoke active_record

create db/migrate/20160303132302_change_column_is_holiday_to_days.rb

class ChangeColumnIsHolidayToDays &lt; ActiveRecord::Migration
  def change
    rename_column :days, :is_holiday, :holiday
  end
end

class ChangeColumnIsHolidayToDays < ActiveRecord::Migration

def change

rename_column :days, :is_holiday, :holiday

end