Draw an E-R diagram to represent the sample customer order shown on FIGURE 8-4. Please use Microsoft Visio if you can, and include the information from the sample customer order. Thanks so much!

You can also gather the information you need for data modeling by review- ing specific business documents-computer displays, reports, and business forms- handled within the system. This process of gaining an understanding of data is often called a bottom-up approach. These items will appear as data flows on DFDs and will show the data processed by the system and, hence, probably the data that must be maintained in the system's database. Consider, for example, Figure 8-4, which shows a customer order form used at Pine Valley Furniture (PVF). From this form, we deter- mine that the following data must be kept in the database: ORDER NO ORDER DATE PROMISED DATE PRODUCT NO DESCRIPTION QUANTITY ORDERED UNIT PRICE CUSTOMER NO NAME ADDRESS CITY-STATE-ZIP