Any organization that uses the Oracle relational database management system (RDBMS) these days needs to use multiple databases. There are many reasons to use more than a single database in a distributed database system-
*Different databases may be associated with particular business functions, such as manufacturing or human resources.
*Databases may be aligned with geographical boundaries, such as a behemoth database at a headquarters site and smaller databases at regional offices.
*Two different databases may be required to access the same data in different ways, such as an order entry database whose transactions are aggregated and analyzed in a data warehouse.
*A busy Internet commerce site may create multiple copies of the same database to attain horizontal scalability.
*A copy of a production database may be created to serve as a development test bed.
In a distributed database environment, data in two or more databases is accessible as if it were in a single database. Usually, the different databases are on different servers, which may be located at the same site or a continent away. Communication between the servers takes place via SQL*Net (for Oracle7) or Net8 (for Oracle8).
Distributed database environments offer a number of benefits over single- database systems, including-
This book describes how you can use multiple databases and the distributed features of Oracle to best advantage. It covers-
Table of contents-
Part I- The Distributed System
1. Introduction to Distributed Database Systems 2. SQL*Net and Net8 3. Configuration and Administration 4. Distributed Database Security 5. Designing the Distributed System 6. Oracle's Distributed System Implementation 7. Sample Configurations 8. Engineering Considerations
Part II- Replication
9. Oracle Replication Architecture 10. Advanced Replication Option Installation 11. Basic Replication 12. Multi-Master Replication 13. Updateable Snapshots 14. Procedural Replication 15. Conflict Avoidance and Resolution Techniques
Part III- Appendixes
Appendix A- Built-in Packages for Distributed Systems Appendix B- Scripts