Update ved hjælp af cursor

Jeg forstår ikke helt hvorfor det går galt. Kan en eller anden forklare mig det?

BEGIN TRAN

DECLARE @MType as nvarchar(30)
DECLARE @MName as nvarchar(30)

DECLARE ChangeNames CURSOR
FOR
SELECT HW_Model_Name_VC, HW_Model_Type_VC
FROM HW_Model_T

OPEN ChangeNames

FETCH NEXT FROM ChangeNames INTO @MName, @MType

WHILE @@FETCH_STATUS = 0
BEGIN
    UPDATE Table1
    SET Table1_Name = @MName
    WHERE Table1_Type = @MType
FETCH NEXT FROM ChangeNames INTO @MName, @MType
END

CLOSE ChangeNames
DEALLOCATE ChangeNames