title: Transact-SQL to sum up elapsed time
body: <p>I have a table in my database the records start and stop times for a specific task.  Here is a sample of the data:</p>
  
  <pre><code>Start                       Stop
  9/15/2008 5:59:46 PM        9/15/2008 6:26:28 PM
  9/15/2008 6:30:45 PM        9/15/2008 6:40:49 PM
  9/16/2008 8:30:45 PM        9/15/2008 9:20:29 PM
  9/16/2008 12:30:45 PM       12/31/9999 12:00:00 AM
  </code></pre>
  
  <p>I would like to write a script that totals up the elapsed minutes for these time frames, and wherever there is a 12/31/9999 date, I want it to use the current date and time, as this is still in progress.</p>
  
  <p>How would I do this using Transact-SQL?</p>