Query Employee With Birthdate in the Next 7 days

DECLARE @TODAY INT = DATEPART(DAYOFYEAR, GETDATE())

DECLARE @DAYSINYEAR INT = DATEPART(DAYOFYEAR, DATEADD(DAY, -1 , DATEFROMPARTS(DATEPART(YEAR, DATEADD(YEAR, 1, GETDATE())), 1, 1)))

SELECT [DATE_OF_BIRTH]

FROM EMPLOYEE

WHERE (CASE WHEN DATEPART(DAYOFYEAR, [DATE_OF_BIRTH]) < @TODAY

            THEN DATEPART(DAYOFYEAR, [DATE_OF_BIRTH]) + @DAYSINYEAR

            ELSE DATEPART(DAYOFYEAR, [DATE_OF_BIRTH]) END)

      BETWEEN @TODAY and @TODAY + 6