SUM ROWS OF VARCHAR DATATYPE or TIME DATATYPE in MYSQL

Question

My table CalTime has a column Timespent which is of Time datatype. It stores values in HH:MM:SS format. Please suggest how can sum the values of this column.

   Timespent
    _______
    00:07:00
    01:05:00
    00:49:00

I want to print the total like this 02:01:00.

I wonder if there is an alternative to this using php..

PS: I tried doing it with php, converting each column value (in while loop ) into timestamp using strtotime and then adding them and converting them back to required format as HH:MM:SS using date('H:i:s'). That does not seem to work. Code look something like this.

     <?php   while(...)
      {
      $ts += strtotime($timeCal['timespent']);
      } ?>

Answer 1

Transform it in seconds, then sum it,then back to time:

SELECT  SEC_TO_TIME( SUM( TIME_TO_SEC( `timespent` ) ) ) AS timeSum  
FROM CalTime

Answer 2

Here is a simple functionality for this. You can loop through your values in an array to keep adding to the below code.

//Incase strtotime gives any errors
date_default_timezone_set('America/New_York');
//
$mytime1 = "00:07:00";
$mytime2 = "01:05:00";
$secs = strtotime($mytime2)-strtotime("00:00:00");
$result = date("H:i:s",strtotime($mytime1)+$secs);

Psuedocode Example in a loop.
Return mysql results in the php array

$mytime1 = $myTimeArray[0]; 
$result = 0;

for($i=0;i<sizeOf($myTimeArray;$i++)) {
   $secs = strtotime($mytime[$i])-strtotime("00:00:00");
   $result + = date("H:i:s",strtotime($mytime1)+$secs);
}