title: Get the time difference between the first and last row
body: <p>My table structure is like this</p>
  
  <pre><code>id date         Time                userid
  
  17  2017-01-22  05:08:09.0000000    836232017
  16  2017-01-22  05:08:05.0000000    836232017
  11  2017-01-22  05:06:40.0000000    836232017
  10  2017-01-22  05:06:38.0000000    836232017
  7   2017-01-22  05:06:31.0000000    836232017
  </code></pre>
  
  <p>I need to get the time difference between the first and last value for the corresponding userid and date. 
  Eg: the datediff for the userid 836232017 is between '05:08:09.0000000' and 
  '05:06:31.0000000'. Please provide a solution for this.</p>