I want to create Parameters using Custom SQL. But,I found, "Order By" Is not working. How , I can sort Dates. I want Descending order.

I want to create Parameters using Custom SQL. But,I found, Order By Is not working. How , I can sort Dates. I want Descending order.

I want to show Dates in descending Order. Eg: 7/30/2015,7/29/2015,7/28/2015 in Drop down in Date Parameter