Materialized view

[Sultan Syed]

Hi   How can I create materialized view(mv) for the following statement using 'refresh fast' method. I can use  'refresh complete'   option to create this mv, but how can I use 'refresh fast' option for the below statement in order to improve performance in query. Any workaround ?   select mas.salesrep_id,sum(del.qty*del.price)-sum(del.discount) from sales_master mas, sales_details del where mas.transaction_id =del.transaction_id group by mas.salesrep_id. Thanks in advance