DECLARE @dt DATETIME
SET @dt = GETDATE()
SELECT
	CAST(CAST(YEAR(@dt) AS CHAR(4))+'0101' AS DATETIME) 
		AS Jahresanfang
	, CAST(CAST(YEAR(@dt) AS CHAR(4))+'-12-31T23:59:59.997' AS DATETIME) 
		AS Jahresende 

Jahresanfang                                           Jahresende               
------------------------------------------------------ ------------------------ 
2004-01-01 00:00:00.000                                2004-12-31 23:59:59.997

(1 row(s) affected)