1. Copyright © 2004 Pearson Education, Inc.

2. Chapter 25 Distributed Databases and Client–Server Architectures

3. Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition Copyright © 2004 Pearson Education, Inc. Slide 25-3 Distributed Database Concepts Parallel Versus Distributed Technology Advantages of Distributed Databases Additional Functions of Distributed Databases

4. Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition Copyright © 2004 Pearson Education, Inc. Slide 25-4 Data Fragmentation, Replication, and Allocation Techniques for Distributed Database Design Data Fragmentation Data Replication and Allocation Example of Fragmentation, Allocation, and Replication

5. Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition Copyright © 2004 Pearson Education, Inc. Slide 25-5 Types of Distributed Database Systems

6. Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition Copyright © 2004 Pearson Education, Inc. Slide 25-6 Query Processing in Distributed Databases Data Transfer Costs of Distributed Query Processing Distributed Query Processing Using Semijoin Query and Update Decomposition

7. Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition Copyright © 2004 Pearson Education, Inc. Slide 25-7 Overview of Concurrency Control and Recovery in Distributed Databases Distributed Concurrency Control Based on a Distinguished Copy of a Data Item Distributed Concurrency Control Based on Voting Distributed Recovery

8. Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition Copyright © 2004 Pearson Education, Inc. Slide 25-8 An Overview of 3-Tier Client- Server Architecture

9. Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition Copyright © 2004 Pearson Education, Inc. Slide 25-9 Distributed Databases in Oracle

10. Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition Copyright © 2004 Pearson Education, Inc. Slide 25-10 Summary