title: How to update all when you need callbacks fired?
body: <p>Let's say I've got 15 user ids in an array called <code>user_ids</code>.</p>
  
  <p>If I want to, say, change all of their names to "Bob" I could do:</p>
  
  <pre><code>users = User.find(user_ids)
  users.update_all( :name =&gt; 'Bob' )
  </code></pre>
  
  <p>This doesn't trigger callbacks, though. If I need to trigger callbacks on these records saving, to my knowledge the only way is to use:</p>
  
  <pre><code>users = User.find(user_ids)
  users.each do |u|
    u.name = 'Bob'
    u.save
  end
  </code></pre>
  
  <p>This potentially means a very long running task in a controller action, however.</p>
  
  <p>So, my question is, is there any other better / higher performance / railsier way to trigger a batch update to a set of records that <em>does</em> trigger the callbacks on the records?</p>