title: Rails Migration with adding and removing reference
body: <p>After creating a migration file with <code>rails generate migration AddClientToUser</code> I can edit my migration file like so:</p>
  
  <pre><code>class AddClientToUser &lt; ActiveRecord::Migration
    def self.up
      change_table :users do |t|
        t.references :client
      end
    end
  
    def self.down
      change_table :users do |t|
        t.remove :client_id
      end
    end
  end
  </code></pre>
  
  <p>Is this the correct way to reverse the reference column added in the migration?</p>