Utilice la siguiente consulta:
DECLARAR en fecha DOB = ‘1994-05-26’
SELECCIONE @DOB AS DateOfBirth, cast (getdate () AS Date) AS TillDate, datediff (month, @ DOB, cast (getdate () AS Date)) MonthDiff, (monthfiff, month, @ DOB, cast (getdate () AS Fecha)) / 12) AS Edad