Hour 4, The Normalization Process

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	Sams Teach Yourself SQL in 24 Hours, Third Edition By Ronald R. Plew, Ryan K. Stephens
	Table of Contents
	Appendix C.  Answers to Quizzes and Exercises

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Hour 4, "The Normalization Process"

Quiz Answers

1:	True or false: Normalization is the process of grouping data into logical related groups.
A1:	True.
2:	True or false: Having no duplicate or redundant data in a database, and having everything in the database normalized, is always the best way to go.
A2:	False. Not always; normalization can and does slow performance because more tables must be joined which results in more I/O and CPU time.
3:	True or false: If data is in the third normal form, it is automatically in the first and second normal forms.
A3:	True.
4:	What is a major advantage of a denormalized database versus a normalized database?
A4:	Improved performance.
5:	What are some major disadvantages of denormalization?
A5:	Having redundant and duplicate data takes up valuable space; it is harder to code, and much more data maintenance is required.

Exercise Answers

1:

You are developing a new database for a small company. Take the following data and normalize it. Keep in mind that there would be many more items for a small company than you are given here.

Employees:

Angela Smith, secretary, 317-545-6789, RR 1 Box 73, Greensburg, Indiana, 47890, $9.50 hour, date started January 22, 1996, SSN is 323149669.

Jack Lee Nelson, salesman , 3334 N Main St, Brownsburg, IN, 45687, 317-852-9901, salary of $35,000.00 year, SSN is 312567342, date started 10/28/95.

Customers:

Robert's Games and Things, 5612 Lafayette Rd, Indianapolis, IN, 46224, 317-291-7888, customer ID is 432A.

Reed's Dairy Bar, 4556 W 10th St, Indianapolis, IN, 46245, 317-271-9823, customer ID is 117A.

Customer Orders:

Customer ID is 117A, date of last order is December 20, 1999, product ordered was napkins and the product ID is 661.

A1:

Employees	Customers	Orders
SSN	CUSTOMER ID	CUSTOMER ID
NAME	NAME	PRODUCT ID
STREET ADDRESS	STREET ADDRESS	PRODUCT
CITY	CITY	DATE ORDERED
STATE	STATE
ZIP	ZIP
PHONE NUMBER	PHONE NUMBER
SALARY
HOURLY PAY
START DATE
POSITION

2:

Navigate to the folder on your computer where you installed MySQL, and then to the bin folder. Double-click on the mysql.exe executable to invoke MySQL. Then type the following at the command prompt to use your database:

  use learnsql;  

3:

At the mysql> prompt, enter CREATE TABLE statements based on the tables you defined in Exercise 1.

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