title: CI Is there a way to query custom order_by
body: <p>Is it possible to customize the order_by query in MySQL or in CI ? Such as I want my column to be ordered by ('1', '11', '4', '2', '21', '3', '5', '7') So if I query it as ASC the result will show in the order of my customized order.</p>
  
  <p>If it is not possible, what is the best workaround to get these order ? Hoping for a simple solution just using the MySQL query.</p>
  
  <p>All answers and suggestions are greatly welcomed. Thanks.</p>