title: Fast way to get the current voting rank?
body: <p>I've a video model which has a votes_count. I already have a method which fetches the current rank.</p>
  
  <pre><code>def rank
    videos = Video.order('votes_count DESC')
    videos.index(self)+1
  end
  </code></pre>
  
  <p>Is there a simpler solution which uses less cpu?</p>
  
  <p>Thanks in advance</p>