SQL Server中获取第一天、最后一天

SELECT DATEADD(mm, DATEDIFF(mm,0,getdate()), 0) 

SELECT DATEADD(wk, DATEDIFF(wk,0,getdate()), 0)

SELECT DATEADD(yy, DATEDIFF(yy,0,getdate()), 0)

SELECT DATEADD(qq, DATEDIFF(qq,0,getdate()), 0)

SELECT DATEADD(dd, DATEDIFF(dd,0,getdate()), 0)

SELECT dateadd(ms,-3,DATEADD(mm, DATEDIFF(mm,0,getdate()), 0)) 

SELECT dateadd(ms,-3,DATEADD(yy, DATEDIFF(yy,0,getdate()), 0)) 

SELECT dateadd(ms,-3,DATEADD(mm, DATEDIFF(m,0,getdate())+1, 0))

SELECT dateadd(ms,-3,DATEADD(yy, DATEDIFF(yy,0,getdate())+1, 0)) 

select DATEADD(wk, DATEDIFF(wk,0,dateadd(dd,6-datepart(day,getdate()),getdate())), 0)