Note: You do not need to show all attributes in your ER design, but you must show any participation and cardinality relationships. If you need to make additional assumptions about the application in order to develop your ER diagram, please do so.
The following requirements were considered in the design of the model for books: we must maintain their ISBN, title, author(s), and year of publication. We also need to know how many copies of each book are currently in stock in the warehouse and available for delivery, as well as the current price for customers. We need to know their names and shipping addresses. Customers can deal with the bookstore either online or offline, simply by phone. They can place their orders through the customer service department or deal with the bookstore directly by phone. The above information is all that is required.
In addition to the customer information for orders, there is an ID that we need to remember. We need to know who placed the order, when they placed it, when the order was shipped, and whether they have paid for the order. Orders are only shipped when all ordered items are available. Multiple copies of a given book may be ordered.
