Chapter 1. The Database Environment
Can you think of a business that doesn't have a database that's stored on a computer? Maybe you can't, but I know of one: a small used paperback bookstore. A customer brings in used paperbacks and receives credit for them based on their condition and, in some cases, the subject matter of the books. That credit can be applied to purchasing books from the store at approximately twice what the store pays to acquire the books. The books are shelved by general type (for example, mystery, romance, and nonfiction), but otherwise they are not categorized. The store doesn't have a precise inventory of what is on its shelves.
To keep track of customer credits, the store has a 4 × 6 card for each customer on which employees ...

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