Question

我已经忙了好几个小时，但是我无法让它工作。

SQL

SELECT DATEDIFF(end_time, start_time) as `difference` FROM timeattendance WHERE timeattendance_id = '1484'

start_time =   2012-01-01   12:00:00
end_time =     2012-01-02   13:00:00

差异是25（小时）。但我得到的输出是1（天）。

如何获得25小时的输出？

Answer 1

如何使用TIMESTAMPDIFF？

SELECT TIMESTAMPDIFF(HOUR, start_time, end_time) 
           as `difference` FROM timeattendance WHERE timeattendance_id = '1484'

Answer 2

您最好使用TIMEDIFF而不是DATEDIFF，因为DATEDIFF会在比较之前将所有时间都转换为日期。执行TIMEDIFF后，您可以获得具有HOUR功能的小时数。

SELECT HOUR(TIMEDIFF(end_time, start_time)) as `difference`;

Answer 3

正如MySQL reference中所述，DATEDIFF只需要几天的时间。

如果两个日期都在1970年之后，您可以减去时间戳：

SELECT ( UNIX_TIMESTAMP("2012-01-02 13:00:00") - 
         UNIX_TIMESTAMP("2012-01-01 12:00:00") ) / 3600 ...

或：

SELECT TIMEDIFF ( "2012-01-02 13:00:00", "2012-01-01 12:00:00") / 3600 ...

Answer 4

您可以使用TIMEDIFF和HOUR功能来提取小时。

SELECT HOUR(TIMEDIFF(end_time, start_time)) as `difference` FROM timeattendance WHERE timeattendance_id = '1484'

http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_timediff
http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_hour

仅在MYSQL DATEDIFF中显示小时数

4 个答案: