db/migrate/20150111192335_subscribe_old_changesets.rb

   1 class SubscribeOldChangesets < ActiveRecord::Migration[5.0]
   2   def up
   3     Changeset.find_each do |changeset|
   4       changeset.subscribers << changeset.user unless changeset.subscribers.exists?(changeset.user.id)
   5     end
   6   end
   7
   8   def down; end
   9 end