DECLARE @v1 datetime, @v2 datetime
SET @v1 = '1981-05-05'
SET @v2 = '1980-01-01'
SELECT datediff(yy, @v2, @v1), datediff(mm, @v2, @v1),datediff(dd, @v2, @v1)
SET @v1 = '1981-05-05'
SET @v2 = '1980-01-01'
SELECT datediff(yy, @v2, @v1), datediff(mm, @v2, @v1),datediff(dd, @v2, @v1)
DECLARE @v1 datetime, @v2 datetime
SET @v1 = '1981-05-05'
SET @v2 = '1980-01-01'
SELECT cast(@v1 - @v2 as int)这样就可以得到相差的天数,是一个整数。要得到相差的年,月等,可以用datediff函数。
所以他们相减必然也是得到数据类型datetime