Order Entry (OE)

The company sells several categories of products, including computer hardware and software, music, clothing, and tools. The company maintains information that includes product identification numbers, the category into which the product falls, the weight group (for shipping purposes), the warranty period if applicable, the supplier, the availability status of the product, a list price, a minimum price at which a product will be sold, and a URL address for manufacturer information. Inventory information is also recorded for all products, including the warehouse where the product is available and the quantity on hand. Because products are sold worldwide, the company maintains the names of the products and their descriptions in several languages.

The company maintains warehouses in several locations to facilitate filling customer orders. Each warehouse has a warehouse identification number, name, facility description, and location identification number.

Customer information is tracked in some detail. Each customer is assigned an identification number. Customer records include name, street address, city or province, country, phone numbers (up to five phone numbers for each customer), and postal code. Some customers order through the Internet, so email addresses are also recorded. Because of language differences among customers, the company records the native language and territory of each customer.

The company places a credit limit on its customers to limit the amount they can purchase at one time. Some customers have an account manager, and this information is also recorded.

When a customer places an order, the company tracks the date of the order, how the order was placed, the current status of the order, shipping mode, total amount of the order, and the sales representative who helped place the order. The sales representative may or may not be the same person as the account manager for a customer. In the case of an order over the Internet, no sales representative is recorded. In addition to the order information, the company also tracks the number of items ordered, the unit price, and the products ordered.

For each country in which it does business, the company records the country name, currency symbol, currency name, and the region where the county resides geographically. This data is useful customers living in different geographic regions around the world.

Online Catalog (OC) Description

The OC subschema of the OE schema addresses an online catalog merchandising scenario. The same customers and products are used as in the OE schema proper, but the OC subschema organizes the categories to which the OE products belong into a hierarchy of parent categories and subcategories. This hierarchy corresponds to the arrangement on an e-commerce portal site, where users navigate to specific products by drilling down through increasingly specialized categories of products.