Fundamentals of Database Management Systems, Second Edition

CHAPTER 12

CLIENT/SERVER DATABASE AND DISTRIBUTED DATABASIE

Simply put, the question in this chapter is, “Where is the database located?” I Often, the obvious answer is, “It's in the computer itself!” That is, it is located on one of the computer's disk drives. If the computer in question is a stand-alone personal computer, of course the database is stored on the PC's hard drive or perhaps on a flash disk. (Where else could it be?!) The same can be and often is true of much larger computer systems. A company can certainly choose to have its databases stored in its mainframe computer, while providing access to the computer and its databases on a broad, even worldwide scale. This chapter will describe alternative arrangements in which the data is decentralized and not stored in one central location.

OBJECTIVES

• Describe the concepts and advantages of the client/server database approach.
• Describe the concepts and advantages of the distributed database approach.
• Explain how data can be distributed and replicated in a distributed database.
• Describe the problem of concurrency control in a distributed database.
• Describe the distributed join process.
• Describe data partitioning in a distributed database.
• Describe distributed directory management.

CHAPTER OUTLINE

Introduction

Client/Server Databases

Distributed Database

• The Distributed Database Concept
• Concurrency Control in Distributed Databases
• Distributed Joins
• Partitioning or Fragmentation
• Distributed Directory Management
• Distributed ...