title: Query on date or does not exist?
body: <p>Trying to figure out if I can make this query work using mongoose and nodejs.</p>
  
  <pre><code>   Product.find({
          price: { $gt: 2, $lt: 3},
          date: { $gt: new Date() || $exists: false}
      }). exec(callback);
  </code></pre>
  
  <p>Does anyone know if it is possible to check if a date does not exist send it back or if the date is greater than today?</p>
  
  <p>Thanks</p>