title: Mongoose: Running Scheduled Job Query by Date
body: <p>I want to create a scheduled job for patients in a hospital. The patients will be informed every month by their <code>reg_date</code>. </p>
  
  <p>I'm using <code>new Date().getDate()</code> inside my scheduled Jobs to run at 8.00 AM in the morning to send SMS to my patients. Meanwhile, I had been using string format date to save <code>reg_date</code> in my mongoDB. Here is snippets of my mongoDB docs :</p>
  
  <pre><code>{
      customer: "John",
      reg_date: "2017-02-17T16:39:26.969Z"
  }
  </code></pre>
  
  <p>I've ben surfing for solutions but it turns out nothing, so I decided to post myself. Here is what i am trying to do :</p>
  
  <pre><code>customer.find({"reg_date.getDate()" : new Date(2017, 03, 17).getDate()})
      .then(function(data) {
        for (var key in data.length) {
            sendTheSMS(key[data]);
        };
      });
  </code></pre>
  
  <p>E.g: What I am doing is "I want to get every patient who register at 17th day of the month and send them a SMS".</p>
  
  <p>Any help will be appreciated. :D</p>