title: How to sort a mongodb query result in ascending order of age, without a createdAt field? (new to old)
body: <p>When you do a mongodb query, you normally get the results in descending order of age(old to new). How can I get it in the ascending order? </p>
  
  <p>I know that I can save the createdAt timestamp and do a </p>
  
  <pre><code>  .sort({createdAt:-1})
  </code></pre>
  
  <p>on the query to do this, but saving the cretedAt timestamp seperately when the information is already present in _id seems like overkill.</p>
  
  <p>Is there a way to get the results in the ascending order of age (new to old) without using a createdAt timestamp?</p>