List out the discount levels applied for all orders from Ole Group.
Ole Group is the name of the customer; discount levels applied refer to Discount Applied NOT NULL;
SELECT T FROM ( SELECT DISTINCT CASE  WHEN T1.`Customer Names` = 'Ole Group' THEN T2.`Discount Applied` END AS T FROM Customers T1 INNER JOIN `Sales Orders` T2 ON T2._CustomerID = T1.CustomerID ) WHERE T IS NOT NULL