title: Compare two fields in Waterline/Sails.js query
body: <p>I want to compare two fields in my Waterline query in Sails.js application, e.g.: <code>SELECT * FROM entity E WHERE E.current &lt; E.max</code>.</p>
  
  <p>I've tried the following code, but it's expecting integer value to be passed to it instead of column name:</p>
  
  <pre class="lang-javascript prettyprint-override"><code>Entity.find({
    where: {
      current: {'&lt;': 'max'}
    }
  });
  </code></pre>
  
  <p>So, how do I compare two columns?</p>