customers arrive on Willie’s store, they may be helped by any available salesperson. If more than one salesperson helps the same customer with the same merchandise, any resulting sale to that customer will be credited to all involved salespeople, who will split the sale commission. A sale cannot be made without a salesperson and cannot be involved in more than one customer, but the customer still can make multiple sales in a visit. Information about sales, salespeople, and customers often need to be entered into a database before any transaction involving them have occurred. The following data items (attributes) are of interest for this model:
