Sqlserver獲取當月第一天

SELECT DATEADD(month, DATEDIFF(month, 0, GETDATE()), 0) AS StartOfMonth
SELECT DATEFROMPARTS(YEAR(GETDATE()),MONTH(GETDATE()),1)
SELECT DATEADD(DAY,1,EOMONTH(GETDATE(),-1))
SELECT GETDATE()-10 - DAY(GETDATE()) + 1