Database-System Applications

Databases are widely used. Here are some representative applications:

1. Enterprise Information

• Sales: For customer, product, and purchase information.?

• Accounting: For payments, receipts, account balances, assets and other

          accounting information.

• Human resources: For information about employees, salaries, payroll taxes,

and benefits, and for generation of paychecks.

• Manufacturing: For management of the supply chain and for tracking

production of items in factories, inventories of items inwarehouses and stores,

and orders for items.

• Online retailers: For sales data noted above plus online order tracking,

generation of recommendation lists, and maintenance of online product

evaluations.

2.? Banking and Finance

• Banking: For customer information, accounts, loans, and banking transactions.

• Credit card transactions: For purchases on credit cards and generation of

monthly statements.

• Finance: For storing information about holdings, sales, and purchases of

financial instruments such as stocks and bonds; also for storing real-time

market data to enable online trading by customers and automated trading

by the firm.

3. Universities:

• For student information, course registrations, and grades (in

addition to standard enterprise information such as human resources and

accounting).

4. Airlines:

• For reservations and schedule information. Airlines were among the

first to use databases in a geographically distributed manner.

5. Telecommunication:

• For keeping records of calls made, generating monthly

bills, maintaining balances on prepaid calling cards, and storing information

about the communication networks.

As the list illustrates, databases form an essential part of every enterprise today,
storing not only types of information that are common to most enterprises, but
also information that is specific to the category of the enterprise.

Over the course of the last four decades of the twentieth century, use of
databases grewin all enterprises. In the early days, very few people interacted directly
with database systems, although without realizing it, they interacted with
databases indirectly—through printed reports such as credit card statements, or
through agents such as bank tellers and airline reservation agents. Then automated
teller machines came along and let users interact directly with databases.
Phone interfaces to computers (interactive voice-response systems) also allowed
users to deal directly with databases—a caller could dial a number, and press
phone keys to enter information or to select alternative options, to find flight
arrival/departure times, for example, or to register for courses in a university.

The Internet revolution of the late 1990s sharply increased direct user access to
databases. Organizations converted many of their phone interfaces to databases
into Web interfaces, and made a variety of services and information available
online. For instance, when you access an online bookstore and browse a book or
music collection, you are accessing data stored in a database. When you enter an
order online, your order is stored in a database.When you access a bankWeb site
and retrieve your bank balance and transaction information, the information is
retrieved from the bank’s database system.When you access aWeb site, informa-
tion about you may be retrieved from a database to select which advertisements
you should see. Furthermore, data about your Web accesses may be stored in a
database.

Thus, although user interfaces hide details of access to a database, and most
people are not even aware they are dealing with a database, accessing databases
forms an essential part of almost everyone’s life today.
The importance of database systems can be judged in another way—today,
database system vendors like Oracle are among the largest software companies
in the world, and database systems form an important part of the product line of
Microsoft and IBM.

Frequently Asked Questions