Beginning Database Design Solutions

Appendix A. Exercise Solutions

Chapter 1

Exercise 1 Solution

The following list summarizes how the book provides (or doesn't) database goals:

• CRUD: This book doesn't let you easily CREATE information. You could write in new information but there isn't much room for that and that's not really its purpose. The book lets you READ information, although it's hard for you to find a particular piece of information (unless it is listed in the table of contents or the index). You can UPDATE information by crossing out the old information and entering the new. You can also highlight key ideas by underlining, by using a highlighter, and by putting bookmarks on key pages. Finally, you can DELETE data by crossing it out.

• Retrieval: The book's mission in life is to let you retrieve its data, although it can be hard to find specific pieces of information unless you have bookmarked them, or they are in the table of contents or the index.

• Consistency: I've tried hard to make the book's information consistent. If you start making changes, however, it will be extremely hard to ensure that you make related changes to other parts of the book.

• Validity: The book provides no data validation. If you write in new information, the book cannot validate your data. (If you write, "Normalization rocks!" the book cannot verify that it indeed rocks.)

• Easy Error Correction: Correcting one error is easy; simply cross out the incorrect data and write in the new data. Correcting systematic errors (for example, if I've methodically ...