title: How can I sum time in MySQL?
body: <p><img src="https://i.stack.imgur.com/Vo5eP.jpg" alt="DOWNTIME"></p>
  
  <p>As you can see in the image I have a downtime report that shows downtime of the selected mill for the selected date. Now I want to add all the values in the <code>"Time Duration"</code> column and show it in a separate display near <code>"TOTAL TIME DURATION"</code>. For example, in the image, the selected dates are 17th March 2015 and 30th March 2015 and the selected mill is Raw Mill. the report shows the downtime for Raw Mill for the selected 13 days. I want to add all the time in the <code>"Time duration"</code> column for these 13 days and show it in a separate display near <code>"TOTAL TIME DURATION"</code>. The time format is HH:MM:SS. How can I do this? </p>