title: Active Record Query where value in array field
body: <p>I have a table called " Stat " in my MongoDB database in Rails 3 .</p>
  
  <p>In that table, there is an array field called "services" . </p>
  
  <p>I want to find all Stats that have a services array that contains the value "lights" . </p>
  
  <p>I want to do something like this : </p>
  
  <pre><code>@stats = Stat.all
  @stats1 =  @stats.where("services contains lights")
  Rails.logger.info "result:  #{@stats1.count}  " 
  </code></pre>
  
  <p>I've tried various things and Googled it extensively, found some leads but nothing that seems to work. I have four records that should match this query but the above returns a zero set. </p>
  
  <p>Is what I want to do possible in rails 3 / mongo ? </p>