sqlserver 计算资料库时间差

datediff(datepart,startdate,enddate) 返回间隔 datepart 的数
SELECT datediff(yy,’2010-06-1 10:10′,GETDATE()) –计算多少年
SELECT datediff(q,’2011-01-1 10:10′,GETDATE())  –计算多少季度 3 个月一个季度
SELECT datediff(mm,’2011-06-1 10:10′,GETDATE()) –计算多少月
SELECT datediff(dd,’2011-06-1 10:10′,GETDATE()) –计算多少天
SELECT datediff(wk,’2011-06-1 10:10′,GETDATE()) –计算多少周
SELECT datediff(hh,’2011-06-10 10:10′,’2011-06-10 11:10′) –计算多少小时
SELECT datediff(n,’2011-06-10 10:10′,’2011-06-10 10:11′) –计算多少分钟
SELECT datediff(ss,’2011-06-10 10:10:00′,’2011-06-10 10:10:10′) –计算多少秒
SELECT datediff(ms,’2011-06-16 10:10:10′,’2011-06-16 10:10:11′) –计算多少毫秒