sort option in Bex portal
I am executing a query on Enterprise Portal. There are many fields like Asset Main Number (values -- 10001325, 10001365, 10001426 etc...) , Asset Life (2, 5, 6, 8 etc...), Responsible cost center (values -- 2000/87161, 2000/87159, 2000/87162, 2000/8547, etc...).
After Execution on the portal when i right click and do a sort option ( descending / ascending ) it works fine for the fields Asset main number, asset life.
But for the field Responsible cost center it does not work ( does not sort in anyway).
Can anyone please tell me the reason for this to happen?