title: SQL finding the max of the difference of two dates
body: <p>I have two dates (run date) and (date due). I need to find the largest delinquent date which would be the largest (max) number of days between the run date and the due date.</p>
  
  <p>Logically I would want this to be <code>max ( datedif ( day, run date, date due))</code>, however, this code does not seem to run in SQL.</p>
  
  <p>Please help</p>