DATABASES AND THE INTERNET - Fundamentals of Database Management Systems - page 366

INTRODUCTION

Aside from email and file transfers, we associate the Internet with that most
exciting of applications, electronic commerce . It's amazing how we as individuals
can shop online, bank online, get our news online, get all sorts of entertainment
online, and search for every kind of information imaginable, all within the broad
scope of e-commerce. Companies have found new ways of selling to one another,
forming alliances with one another, disposing of excess inventory, and generally
speaking turning the world into a global marketplace. And, the essence of all of
this e-commerce activity is data stored in databases. When you look through a
company's product selections, the data comes from a database. When you place
an order with a company, the order goes into a database. When you check your
bank account balance, you're querying a database. Even reading newspapers online
involves retrieving data from specialized text databases.
The question for us in this chapter is: what makes the Internet database
environment different from a database environment that does not specifically
involve the Internet? Well, first of all, what's not different? The fact is that most (but
not all) e-commerce databases are relational databases and many are transactional
in nature. The concepts of relational databases and the rules for designing relational
databases are the same for transactional e-commerce applications as for any other
transactional applications. SQL and other standard query tools can be and are
used in the e-commerce environment, too. Yet, there are some differences between
the Internet database environment and the non-Internet environment. So, what's
different? We will organize the answer to this question into four categories that will
form the major headings in this chapter:

Database Connectivity Issues ■

Expanded Set of Data Types

■

Database Control Issues

■

Data Extraction into XML

■

14-A S TATE OF T ENNESSEE— D EPARTMENT OF S AFETY

CONCEPTS

IN ACTION

T ennessee, with 5.7 million people
and an area of over 42,000 square miles, is the 16th
largest U.S. state in population and the 36th largest in
area. It became the 16th state of the U.S. in 1796.
Its principal cities are Memphis, Nashville (the capital),
Knoxville, and Chattanooga. Its leading industries include
printing, publishing, chemicals, fabricated metals, and
automobile manufacturing. Almost one-half of the state's
land is dedicated to 80,000 farms, with the major prod-
ucts being cattle, hardwood lumber, dairy products, and
cotton. Centrally located in the U.S., the state is also
known as a major distribution center. As in all states,

the Tennessee state government is responsible for a wide
variety of public services, including the collection and
management of state taxes, the management and main-
tenance of state parks, and the management of various
social services for its citizens. The state's Department of
Safety is responsible for services such as the licensing of
motor vehicles and drivers and the enforcement of laws
covering the operation of motor vehicles.
The Department of Safety maintains a Driver's
License System database application that tracks the state's
driver's licenses. Implemented in 1978, the database
stores basic name and address data as well as data