DISTRIBUTED DATABASE SYSTEMS - Database Design and Development: An Essential Guide for IT Professionals - page 542

CHAPTER 18

DISTRIBUTED DATABASE SYSTEMS

CHAPTER OBJECTIVES

• Understand the fundamental principles of distributed database systems
• Appreciate the motivation and goals for distributing data
• Examine the various types, configurations, and methods for data distribution
• Note how the client/server architecture enables distributed database systems
• Study the features and functions of a distributed database management system
(DDBMS)
• Explore the principle of transparency and grasp its significance
• Learn the implications of query and transaction processing

Refer back to the evolution of database systems in the early 1970s from file-
oriented data systems. Each application had its own set of files; each group of users
accessed the files pertinent to their applications. As business conditions changed
and the demand for information sharing escalated, file-oriented systems became
inadequate. Each user group could not work in isolation. For the overall benefit of
the organization, all user groups needed to share information and collaborate with
one another to achieve the corporate business goals. Decentralization by applica-
tions in file-oriented systems no longer served useful purposes. A centralized data-
base system emerged, and users could share information from the integrated
database and work together. By the late 1980s, many organizations possessed huge,
centralized databases. Tremendous growth in computing technology made this
transition possible.