Customers of 'XXX' supermarket often complain about the long queues at the check-out cashier counters, and the management of 'XXX' is worried about losing customers to its competitors. To cut down customers' queuing time, streamline/increase staff productivity and cut down on labour costs, CEO of 'XXX' is going to develop new self-checkout counters. The following scenario describes the activities or operations for the ideal self-checkout systems:
The customer brings the items to be bought to the front self-checkout machine and starts scanning the barcode on each item one by one. Each time an item's barcode is successfully scanned and read by the machine, the item's name (and its brief description), selling price of the item with any discounts are displayed on the panel screen. The subtotal price of all items barcodes that have been scanned so far will also be displayed on the panel screen. When the customer finishes scanning all items to be bought, the customer selects the payment options which can be cash or credit card. For cash payment, customers insert into the machine the necessary amount of money displayed on the panel screen, the system displays the amount of cash that has been inserted so far by the customer. The system will give out the receipt when full payment is given and money changes (if any). For credit payments, customers scan the credit card on the card reader. If the bank of corresponding credit card confirms the payment, a receipt will be given out. Once receipts have been given out to customers, the inventory will be updated. System will time out after a period of inactivity, and customers can cancel the incomplete transaction before payment is done anytime.
From the above description, draw a data flow diagram showing the flow of input information (and/or data) and output information (and/or data) to and from processes and database stores within this self-checkout system and any external environmental elements that interact with this system. You MUST use SSADM notation - see notes on data flow diagrams.
In this diagram, you must identify the following:
(a) processes inside this self-checkout system,
(24 marks)
(b) database stores, external environmental elements that interact with any of the processes identified in (a)
(11 marks)
(c) input and output information (or data) to and from each of the processes, database stores and external environmental elements identified in (a) and (b),
(17 marks)
(Hint: there are 2 environmental elements that interact with this self-checkout, and SIX main processes in this self-checkout system)
