Touching data in migrations

gistfile1.txt

$ git clone my_repo && cd my_repo
$ bundle install
$ rake db:create
$ rake db:create

=> Oh no! I can't build the db because I don't have any instances of SomeModel. Useless!

some_migration.rb

class SomeMigration < ActiveRecord::Migration
  def self.up
    add_column :some_models, :last_email_sent_at, :datetime
    SomeModel.all.each do |member|
      member.last_email_sent_at = Time.now
      member.current_email_sent_at = Time.now
      member.save false
    end
  end

  def self.down
    # ...
  end
end