Oracle Distributed Systems

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By Charles Dye

Publisher: O'Reilly Media

Released: April 1999

Pages: 552

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:

Tunability
Platform autonomy
Fault tolerance
Scalability
Location transparency
Site autonomy

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

Introduction to Distributed Database Systems
SQL*Net and Net8
Configuration and Administration
Distributed Database Security
Designing the Distributed System
Oracle's Distributed System Implementation
Sample Configurations 8. Engineering Considerations

Part II: Replication

Oracle Replication Architecture
Advanced Replication Option Installation
Basic Replication
Multi-Master Replication
Updateable Snapshots
Procedural Replication
Conflict Avoidance and Resolution Techniques

Part III: Appendixes

Appendix A: Built-in Packages for Distributed Systems Appendix B: Scripts

The Distributed System
1. Chapter 1 Introduction to Distributed Systems
  1. Terminology and Concepts
  2. What Is a Distributed Database System?
  3. Benefits of Distributed Databases
  4. Multiple Schema Versus Multiple Databases
  5. Options for Distributed Data
  6. Perils of Distributed Databases
  7. Differences Between Oracle7 and Oracle8
2. Chapter 2 SQL*Net and Net8
  1. Protocol Overview
  2. Architecture
  3. SQL*Net/Net8 Tuning
  4. Load Balancing
  5. Oracle8 Scalability Options
  6. SQL*Net/Net8 Client Configuration
  7. SNMP Support
  8. Security
3. Chapter 3 Configuration and Administration
  1. Initialization Parameters
  2. Database Links
  3. Distributed Queries and Transactions
  4. Distributed Backup and Recovery
  5. Multiversion Interoperability
4. Chapter 4 Distributed Database Security
  1. Privilege Management
  2. Authentication Methods
5. Chapter 5 Designing a Distributed System
  1. Characteristics of a Distributed System
  2. The Global Data Dictionary
  3. Replication-Specific Issues
  4. Data Partitioning Methodologies
  5. Application Partitioning Strategies
  6. Procedural Replication
6. Chapter 6 Oracle’s Distributed System Implementation
  1. Meeting the 12 Objectives with Oracle
  2. Oracle’s Global Data Dictionary
7. Chapter 7 Sample Configurations
  1. The High-Availability System
  2. Geographic Data Distribution
  3. Workflow Partitioning
  4. Data Collection and Consolidation
  5. Loosely Coupled Federation
8. Chapter 8 Engineering Considerations
  1. Schema Design and Integration
  2. Application Tiering
  3. Designing a Replicated System
Replication
1. Chapter 9 Oracle Replication Architecture
  1. What Is Oracle Replication?
  2. Types of Replication
  3. Architecture Components
  4. Replication of DDL
  5. Oracle8 Enhancements
  6. Oracle8i Enhancements
  7. Alternatives to Replication
2. Chapter 10 Advanced Replication Installation
  1. Initialization Parameters
  2. Redo Logs and Rollback Segments
  3. Size and Placement of Data Dictionary Objects
  4. Administrative Accounts, Privileges, and Database Links
3. Chapter 11 Basic Replication
  1. About Read-Only Snapshots
  2. Prerequisites and Restrictions
  3. Snapshot Creation Basics
  4. Simple Versus Complex Snapshots
  5. Snapshot Logs
  6. Subquery Subsetting
  7. Refresh Groups
  8. Management and Optimization
  9. Scripts
4. Chapter 12 Multi-Master Replication
  1. Concepts and Terminology
  2. Getting Started
  3. Replication Groups
  4. Master Site Maintenance and Propagation
  5. Controlling Propagation
  6. The Replication Catalog
  7. Table Replication
  8. Replicating DDL
  9. Your Replicated Environment
  10. Advanced Replication Limitations
5. Chapter 13 Updateable Snapshots
  1. About Updateable Snapshots
  2. Creating Updateable Snapshots
  3. Communication Flow
  4. Controlling Propagation and Refreshes
  5. Maintenance
6. Chapter 14 Procedural Replication
  1. When to Use Procedural Replication
  2. How Procedural Replication Works
  3. Creating a Replicated Package Procedure
  4. Restrictions on Procedural Replication
  5. An Example
7. Chapter 15 Conflict Avoidance and Resolution Techniques
  1. Data Integrity Versus Data Convergence
  2. Applications That Avoid Conflicts
  3. Types of Conflicts Detected
  4. How Oracle Detects and Resolves Conflicts
  5. Column Groups and Priority Groups
  6. The Built-in Methods
  7. Writing Your Own Conflict Resolution Handler
Appendixes
1. Appendix Built-in Packages for Distributed Systems
  1. DBMS_DEFER: Building Deferred Calls
  2. DBMS_DEFER_QUERY: Performing Diagnostics and Maintenance
  3. DBMS_DEFER_SYS: Managing Deferred Transactions
  4. DBMS_OFFLINE_OG: Performing Site Instantiation
  5. DBMS_OFFLINE_SNAPSHOT: Performing Offline Snapshot Instantiation
  6. DBMS_RECTIFIER_DIFF: Comparing Replicated Tables
  7. DBMS_REFRESH: Managing Snapshot Groups
  8. DBMS_REPCAT: Performing Replication Administration
  9. DBMS_REPCAT_ADMIN: Setting Up Administrative Accounts
  10. DBMS_REPCAT_AUTH: Setting Up More Administrative Accounts
  11. DBMS_REPUTIL: Enabling and Disabling Replication
  12. DBMS_SNAPSHOT: Managing Snapshots
2. Appendix Scripts and Utilities
  1. busycirc.sql
  2. busydisp.sql
  3. busyq.sql
  4. checklatency
  5. colgroups.sql
  6. confstats.sql
  7. cr_regions.sql
  8. defcall.sql
  9. defcalldest.sql
  10. defcallinfo.sql
  11. defdest.sql
  12. deferror.sql
  13. deferror8.sql
  14. deforigin.sql
  15. defschedule.sql
  16. deftran.sql
  17. deftrandest.sql
  18. disprate.sql
  19. errorinfo.sql
  20. fixdefer.sql
  21. gendelerrtran.sql
  22. gendeltran.sql
  23. gengensup.sql
  24. groupedcols.sql
  25. invalids.sql
  26. jobs.sql
  27. keycols.sql
  28. lastsnap.sql
  29. latent.sql
  30. links.sql
  31. mastersnapinfo.sql
  32. mlogs.sql
  33. needsgen.sql
  34. nonrepobjects.sql
  35. pk_regions.sql
  36. prioritygroups.sql
  37. prioritysites.sql
  38. propmode.sql
  39. refgroups.sql
  40. regsnaps.sql
  41. repcaterr.sql
  42. repcatlog.sql
  43. repconflict.sql
  44. repgroup.sql
  45. repobjects.sql
  46. repres.sql
  47. repsites.sql
  48. resconfs.sql
  49. snaps.sql
  50. snaps7.sql
  51. trg_regions.sql
  52. UserAdmin

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