The customer takes the items purchased to the clerk working the point-of-sale (POS) system who rings up the items. The process enters purchase information into the POS system. It transforms the customer purchase and generates a receipt for the customer. After transforming the customer purchase, it also updates the goods sold data in the goods sold file, updates the inventory data in the inventory database, and logs the sales transaction in the sales history file. Whenever the store manager needs a report of the goods sold, inventory, or sales history, the POS system produces them. A high-level DFD, or context diagram of the system is shown.

Use either Microsoft Visio or Word to draw. Visio has all the symbols for a DFD. In Word, select the symbol in the Flowchart group found in AutoShapes of the Drawing Tools that seem closest to the ones for DFDs. For example, the rectangle with rounded corners will resemble the process symbol. A rectangle that is wider than its height will resemble a data store symbol.

Here are the questions.

1. What are the major processes that need to be shown in the level-0 diagram?

2. What are the data stores in the system?

3. Draw the level-0 diagram using Gane and Sarson symbols.

Customer Store Manager Purchase Informatio Point of Sale Management Repo Receipt