1、TIMESTAMPDIFF:后面的时间减去前面的时间 SELECT -- 时间相差不到24小时不算一天 TIMESTAMPDIFF(DAY,'2020-02-25 00:00:00','2020-02-26') day1, -- 1 TIMESTAMPDIFF(DAY,'2020-02-25 00:00:01','2020-02-26') day2, -- 0 TIMESTAMPDIFF(DAY,'