Marcia Wilson owns and operates Marcia’s Dry Cleaning, which is an upscale dry cleaner in a well-to-do suburban neighborhood. Marcia makes her business stand out from the competition by providing superior customer service. She wants to keep track of each of her customers and their orders. Ultimately, she wants to notify them that their clothes are ready via email. Suppose that Marcia has hired you as a database consultant to develop a database for Marcia’s Dry Cleaning that has the following tables:
CUSTOMER (Customer ID, First Name, Last Name, Phone, Email Address) INVOICE (Invoice Number, Customer ID, Date In, Date Out, Subtotal, Tax, Total Amount) INVOICE_ITEM (Invoice Number, Item Number, Service ID, Quantity, Unit Price, Extended Price) SERVICE (Service ID, Service Description, Unit Price)
Assume that all relationships have been defined, as implied by the foreign keys in this table list, and that the appropriate referential integrity constraints are in place.