How to calculate the difference between time in different MySQL columns?

You can use TIME_FORMAT(). Let us first create a table −

mysql> create table DemoTable    -> (    -> PunchIn time,    -> PunchOut time,    -> Launch time    -> ); Query OK, 0 rows affected (0.50 sec)

Insert some records in the table using insert command −

mysql> insert into DemoTable values('9:00','6:00','1:00:00'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('9:30','6:10','00:30:00'); Query OK, 1 row affected (0.21 sec)

Display all records from the table using select statement −

mysql> select *from DemoTable;

Output

+----------+----------+----------+ | PunchIn  | PunchOut | Launch   | +----------+----------+----------+ | 09:00:00 | 06:00:00 | 01:00:00 | | 09:30:00 | 06:10:00 | 00:30:00 | +----------+----------+----------+ 2 rows in set (0.00 sec)

Here is the query to make a correct time calculation −

mysql> SELECT TIME_FORMAT(TIMEDIFF(TIMEDIFF(PunchIn,PunchOut), Launch), '%H:%i') as TimeDiff from DemoTable;

Output

+----------+ | TimeDiff | +----------+ | 02:00    | | 02:50    | +----------+ 2 rows in set (0.00 sec)