Пример выбора диапазона дат:

WITH    q AS
        (
        SELECT  1 AS num
        UNION ALL
        SELECT  num + 1
        FROM    q
        WHERE   num < 10
        )
SELECT  DATEADD(DAY,0,cast(cast(DATEADD(DAY,-num,SYSDATETIME()) as date) as datetime))   
FROM    q