title: Time difference in oracle
body: <p>Hi i have the following table which contains Start time,end time, total time</p>
  
  <hr>
  
  <pre><code>STARTTIME            | ENDTIME             | TOTAL TIME TAKEN  |
  02-12-2013 01:24:00  | 02-12-2013 04:17:00 |  02:53:00         |
  </code></pre>
  
  <hr>
  
  <p>I need to update the <code>TOTAL TIME TAKEN</code> field as above using the update query in oracle</p>
  
  <p>For that I have tried the following select query  </p>
  
  <pre><code>select  round((endtime-starttime) * 60 * 24,2),
          endtime,
          starttime 
    from purge_archive_status_log
  </code></pre>
  
  <p>but I'm getting <strong>02.53</strong> as a result, but my expectation format is <strong>02:53:00</strong> Please let me know how can I do this?</p>