data-migrations-temp-model.rb

class AddAdminToUsers < ActiveRecord::Migration

  # Fill the void
  class User < ActiveRecord::Base
  end unless defined? ::User
  
  def change
    add_column :users, :admin, :boolean, default: false
    
    # convert existing users to admin
    User.reset_column_information
    User.find_each do |u|
      u.update admin: true
    end
  end
end