How to use case without using declare? : I need the ouput  from this.. i knw this is wrong it is just an example
    
    select  customer_name,((Qty * 0.5)*
    (case when (datediff (month, Appointment_Date,getdate())) < 12 )'Incentive' 
    from t1,t2 
    where  t1.customer_code = t2.customer_code