MySQL 如何在不同列中计算时间差

您可以使用TIME_FORMAT()。让我们首先创建一个表 –

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

使用插入命令在表中插入一些记录 –

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)

使用select语句显示表中的所有记录 –

mysql> select *from DemoTable;

阅读更多：MySQL 教程

输出

+----------+----------+----------+
| 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)

这是使正确时间计算的查询 –

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

输出

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