求一个超级难的sql语句(达人请入)

DECLARE @tb TABLE([datetime] datetime, [flag] int)
INSERT INTO @tb
    SELECT  '2006-10-1', 0
    UNION ALL SELECT '2006-10-2', 1
    UNION ALL SELECT '2006-10-3', 0
    UNION ALL SELECT '2006-10-4', 1
    UNION ALL SELECT '2006-10-5', 1
    UNION ALL SELECT '2006-12-29', 0
    UNION ALL SELECT '2006-12-30', 0SELECT TOP 40 [datetime], [flag] FROM @tb ORDER BY flag DESC, [datetime] DESC