周：

Dateadd(wk,datediff(wk,0,getdate()),-1)  Dateadd(wk,datediff(wk,0,getdate()),6) 月：

Dateadd(mm,datediff(mm,0,getdate()),0)  Dateadd(ms,-3,dateadd(mm,datediff(m,0,getdate())+1,0)) 年： Dateadd(yy,datediff(yy,0,getdate()),0)  Dateadd(ms,-3,DATEADD(yy, DATEDIFF(yy,0,getdate())+1, 0))  注：上面的SQL代码只是一个时间段  例：  下面的SQL的条件部分,就是查询时间段在本周范围内的:  Where Time BETWEEN Dateadd(wk,datediff(wk,0,getdate()),-1) AND Dateadd(wk,datediff(wk,0,getdate()),6)  select @begintime = Dateadd(wk,datediff(wk,0,getdate()),-1)  select @endtime = Dateadd(wk,datediff(wk,0,getdate()),6)