我有一个包含参考时间和用户登记时间的表.这两种数据的类型不同.
样本数据
-
dtime
=2023-06-02 08:23:21 -
work_time
=08:00-18:00
我的密码是...
SELECT substring(dtime,-8,5) AS chkin,
SUBSTRING(work_time, 1, 5) AS wt1,
TIMESTAMPDIFF(MINUTE, substring(dtime,-8,5), SUBSTRING(work_time, 1, 5)) AS min_diff
FROM ta_db
WHERE id = 13181;
因此...
-
chkin
=08:23 -
wt1
=08:00
现在,我想知道chkin
分钟和wt
分钟和TIMESTAMPDIFF
分钟有多少不同.
所以我做了这个...
TIMESTAMPDIFF(MINUTE, substring(dtime,-8,5), SUBSTRING(work_time, 1, 5)) AS min_diff
但它返回NULL
.请注意.