时间差计算

DECLARE @a datetime
SET @a = '10:10:00'
SELECT
 时 = s / 60 / 60,
 分 = (s / 60) % 60,
 秒 = s % 60,
 增加差值 = DATEADD(second, s, '2006-1-1')
FROM(
 SELECT s = DATEDIFF(second, @a, 1)
)A
select datediff(second,'23:59:50',1)