title: Django Models auto_now saving same time as auto_now_add
body: <p>Django models issue. I add these 2 fields in almost every model to store created (auto_now_add=True) and updated datetime (auto_now=True).</p>
  <pre><code>created_at = models.DateTimeField(auto_now_add=True) 
  updated_at = models.DateTimeField(auto_now=True, null=True)
  </code></pre>
  <h2>Problem</h2>
  <p>Problem is when I create a new row in a table using Django, created_at field gets populated with current datetime (which is fine) but its updated_at field also gets populated on first time creation.</p>
  <p>Does that make sense? From an end user's point of view, I only created a record but never updated it but in database its updated time is also updated since data is inserted first time in a row (happens whenever you insert a new row). So, when a user views the record, system will show created_at and updated_at exactly same.</p>