title: How to use DateDiff in calculated field in access
body: <p>I am trying to get "No of days late" in a particular table in MS access. I am trying to use calculated data type.</p>
  
  <p>I have [ActualReturnDate] and [ReturnDate] in the same table (both are Date/Time) and I want to save difference between two columns in a calculated field.</p>
  
  <p>I am using following expression:</p>
  
  <pre><code>DateDiff("d", [ActualReturnDate] , [ReturnDate] )
  </code></pre>
  
  <p>But no matter what i do I get error saying "The expression X cannot be used in a calculated column."</p>
  
  <p>So does that mean I cannot use DateDiff in Calculated field? If not how should I do it? </p>