Use this,
DECLARE @start_date DATETIME = '2015-02-12 00:00:00.000';
DECLARE @end_date DATETIME = '2015-02-13 00:00:00.000';
WITH AllDays
AS ( SELECT @start_date AS [Date], 1 AS [level]
UNION ALL
SELECT DATEADD(DAY, 1, [Date]), [level] + 1
FROM AllDays
WHERE [Date] < @end_date )
SELECT [Date], [level]
FROM AllDays OPTION (MAXRECURSION 0)
pass the @start_date and @end_date as SP parameters.
Result:
Date level
----------------------- -----------
2015-02-12 00:00:00.000 1
2015-02-13 00:00:00.000 2
(2 row(s) affected)