Try the following Query
DECLARE @ADate DATETIME
SET @ADate = GETDATE()
DECLARE @Count INT
SELECT @Count=DAY(@ADate)
--Get No of days in Month
DECLARE @rtDate INT
SET @rtDate = CASE WHEN MONTH(@ADate)
IN (1, 3, 5, 7, 8, 10, 12) THEN 31
WHEN MONTH(@ADate) IN (4, 6, 9, 11) THEN 30
ELSE CASE WHEN (YEAR(@ADate) % 4 = 0
AND
YEAR(@ADate) % 100 != 0)
OR
(YEAR(@ADate) % 400 = 0)
THEN 29
ELSE 28 END
END
DECLARE @intFlag INT = 0
WHILE (@intFlag <= @rtDate-1)
BEGIN
SET @intFlag = @intFlag + 1
PRINT @intFlag
END