Read through the following narrative carefully then create a Level 1Logical Data Flow Diagram.
Electron PH is an organization specializing in supplying electronic components. The success of their business depends on a rapid response to their customer’s orders and they are considering the feasibility of updating their current computer system. As a mater of policy Electron PH have no outstanding orders. If parts cannot be delivered when ordered, the order/part order is cancelled and customers must reorder at a later date. Their ordering procedure is as follows:
Customers place orders by post/telephone/fax/mail. The orders are checked on receipt for the correct name, address and customer’s order number. This is carried out using a VDU which queries the customer file to find the Customer’s Number. If the order is from new customer, their name and address is added to the customer file and a new customer’s number is allocated .As the items ordered are given over the telephone or read from the customer’s order form, the stock file is queried to ascertain whether the correct amount of stock is available. If it is, then the item’s part number and description are automatically entered into the order shown on the VDU, and the order is then accepted and the invoice is printed together with a delivery note. When the invoice is printed, the system automatically makes an entry in the sales ledger file under the customer’s number. As there is only one invoice per order ,due to the "no partial order"policy,the invoice number is the same as the order number. The delivery note then sent to the Despatch Department where the goods are picked and packed and the delivery notes are part of a multpart invoice set. The invoice is sent to the customer by mail