MySQL中TIMESTAMPDIFF和DATEDIFF函数的区

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,'2020-02-25  11:00:11','2020-02-26 11:00:11') day3, -- 1
 TIMESTAMPDIFF(DAY,'2020-02-25  11:00:11','2020-02-26 14:00:11') day4, -- 1
 TIMESTAMPDIFF(DAY,'2020-02-25  11:00:11','2020-02-26 10:00:11') day5 -- 0

总结：无论时间单位是什么，不足则不取

2、DATEDIFF：前面的时间减去后面的时间

select 
-- 只取前面日期部分进行计算
 DATEDIFF('2020-02-26','2020-02-25 00:00:00') day1, -- 1
 DATEDIFF('2020-02-26','2020-02-25 00:00:01') day2,  -- 1
 DATEDIFF('2020-02-26 11:00:11','2020-02-25  11:00:11') day3, -- 1
 DATEDIFF('2020-02-26 14:00:11','2020-02-25 11:00:11') day4, -- 1
 DATEDIFF('2020-02-26 10:00:11','2020-02-25  11:00:11') day5 -- 1