mysql - mysql 中的 Timediff 不返回结果

Question

我正在运行此查询:

Select timediff(curtime(),c.approved) From C c WHERE 1=1

我没有得到任何结果，但在我的数据库中我有:

id, approved, Type, file, firstRequest, lastRequest, paymentMethod_id
43, 2012-11-18 14:33:55, CC_Copy, , 2012-11-18 14:33:55, , 1

Answer 1

根据 docs :

TIMEDIFF() returns expr1 – expr2 expressed as a time value. expr1 and expr2 are time or date-and-time expressions, but both must be of the same type.

您正在输入时间 (curtime()) 和日期时间 (approved)。将其更改为

select timediff(curtime(), time(approved)) ...

相反，假设 approved 是日期时间类型，而不是 char/varchar。