Preface

Oracle9i Real Application Clusters Concepts describes the concepts of Real Application Clusters for all operating systems. Read this manual before reading Oracle9i Real Application Clusters Setup and Configuration, Oracle9i Real Application Clusters Administration, and Oracle9i Real Application Clusters Deployment and Performance.

Before reading about Real Application Clusters concepts, however, you should be familiar with single-instance Oracle database processing as described in Oracle9i Database Concepts.

See Also:

The Oracle9i Real Application Clusters Documentation Online Roadmap to use the online Real Application Clusters Documentation set

This preface contains the following topics:

Audience

Real Application Clusters Concepts is intended for database administrators and application developers who work with Real Application Clusters.

Organization

This book presents Real Application Clusters concepts in five parts. It begins by describing cluster database processing fundamentals for Real Application Clusters. The book then describes resource processing among instances. It then explains the fundamentals of implementing Real Application Clusters. Then it describes high availability and Real Application Clusters. The book ends with reference material that includes an appendix describing the implementation restrictions for Real Application Clusters, an appendix on the concepts of lock setting, and a glossary of terms.

Part I "Cluster Database Processing Fundamentals"

Part I introduces Real Application Clusters, describes its architecture and its software components, and explains its scalability features.

Chapter 1, "Introduction to Real Application Clusters"

This chapter introduces cluster database processing with Real Application Clusters.

Chapter 2, "Real Application Clusters Systems Architecture"

This chapter describes the systems components and high-level architectural models that typify cluster environments.

Chapter 3, "Real Application Clusters Software Architecture"

This chapter describes the Real Application Clusters software components.

Chapter 4, "Scalability in Real Application Clusters"

This chapter describes the scalability features of Real Application Clusters.

Part II "Resource Coordination in Real Application Clusters"

Part II describes interinstance resource coordination and explains the processing that the Global Cache Service (GCS) and Global Enqueue Service (GES) perform.

Chapter 5, "Real Application Clusters Resource Coordination"

This chapter describes the interinstance coordination that occur in Real Application Clusters environments.

Chapter 6, "Cache Fusion and the Global Cache Service"

This chapter provides a detailed discussion of Cache Fusion and the interinstance coordination activities managed by the GCS.

Chapter 7, "Resource Coordination by the Global Enqueue Service"

This chapter provides details on and the interinstance coordination activities managed by the GES.

Part III "Implementing Real Application Clusters"

Part III describes the implementation considerations and manageability components for Real Application Clusters.

Chapter 8, "Real Application Clusters Storage Considerations"

This chapter describes the storage considerations for Real Application Clusters applications.

Chapter 9, "Manageability Tools for Real Application Clusters Environments"

This chapter describes the manageability components for Real Application Clusters environments.

Part IV "High Availability and Real Application Clusters"

Part IV describes how you can implement high availability with Real Application Clusters.

Chapter 10, "High Availability Concepts and Best Practices in Real Application Clusters"

This chapter describes the concepts and best practices for using Real Application Clusters to implement high availability.

Part V "Reference"

Part V contains reference information about Real Application Clusters.

Appendix A, "Restrictions"

This appendix lists the deployment restrictions for Real Application Clusters.

Appendix B, "Using Multi-Block Lock Assignments (Optional)"

This appendix describes how to use optional lock setting to override the interinstance coordination provided by Cache Fusion.

Glossary

This glossary defines important terms used in this book.

Related Documentation

After reading this manual, Oracle Corporation recommends that you read Oracle9i Real Application Clusters Setup and Configuration, Oracle9i Real Application Clusters Administration, and Oracle9i Real Application Clusters Deployment and Performance.
You can also read Oracle9i Real Application Clusters Real Application Clusters Guard I - Concepts and Administration for information about Oracle Real Application Clusters Guard I and Oracle9i Real Application Clusters Guard II Concepts, Installation, and Administration on the Real Application Clusters Guard II software CD for information about Real Application Clusters Guard II.

See Also:

The Oracle9i Real Application Clusters Documentation Online Roadmap to use the online Real Application Clusters Documentation set

For more information, see these Oracle resources:

Installation Guides

Oracle9i Installation Guide Release 2 (9.2.0.1) for UNIX Systems: AIX-Based Systems, Compaq Tru64, HP 9000 Series HP-UX, Linux Intel, and Sun Solaris
Oracle9i Database Installation Guide for Windows
Oracle Diagnostics Pack Installation
Oracle Real Application Clusters Guard I installation manuals; there are several platform-specific titles available
Oracle9i Real Application Clusters Guard II Concepts, Installation, and Administration on the Real Application Clusters Guard II software CD

Operating System-Specific Administrator's Guides

Oracle9i Administrator's Reference Release 2 (9.2.0.1) for UNIX Systems: AIX-Based Systems, Compaq Tru64, HP 9000 Series HP-UX, Linux Intel, and Sun Solaris
Oracle9i Database Administrator's Guide for Windows
Oracle9i Real Application Clusters Real Application Clusters Guard I - Concepts and Administration
Oracle9i Real Application Clusters Guard II Concepts, Installation, and Administration on the Real Application Clusters Guard II software CD

Cluster Database Management

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Conventions

This section describes the conventions used in the text and code examples of this documentation set. It describes:

Conventions in Text

We use various conventions in text to help you more quickly identify special terms. The following table describes those conventions and provides examples of their use.

Convention	Meaning	Example
Bold	Bold typeface indicates terms that are defined in the text or terms that appear in a glossary, or both.	When you specify this clause, you create an index-organized table.
Italics	Italic typeface indicates book titles or emphasis.	Oracle9i Database Concepts Ensure that the recovery catalog and target database do not reside on the same disk.
`UPPERCASE monospace (fixed-width) font`	Uppercase monospace typeface indicates elements supplied by the system. Such elements include parameters, privileges, datatypes, RMAN keywords, SQL keywords, SQL*Plus or utility commands, packages and methods, as well as system-supplied column names, database objects and structures, usernames, and roles.	You can specify this clause only for a `NUMBER` column. You can back up the database by using the `BACKUP` command. Query the `TABLE_NAME` column in the `USER_TABLES` data dictionary view. Use the `DBMS_STATS`.`GENERATE_STATS` procedure.
`lowercase monospace (fixed-width) font`	Lowercase monospace typeface indicates executables, filenames, directory names, and sample user-supplied elements. Such elements include computer and database names, net service names, and connect identifiers, as well as user-supplied database objects and structures, column names, packages and classes, usernames and roles, program units, and parameter values. Note: Some programmatic elements use a mixture of UPPERCASE and lowercase. Enter these elements as shown.	Enter `sqlplus` to open SQL*Plus. The password is specified in the `orapwd` file. Back up the datafiles and control files in the `/disk1/oracle/dbs` directory. The `department_id`, `department_name`, and `location_id` columns are in the `hr.departments` table. Set the `QUERY_REWRITE_ENABLED` initialization parameter to `true.` Connect as `oe` user. The `JRepUtil` class implements these methods.
`lowercase italic monospace (fixed-width) font`	Lowercase italic monospace font represents placeholders or variables.	You can specify the `parallel_clause`. Run `U``old_release``.SQL` where `old_release` refers to the release you installed prior to upgrading.

Conventions in Code Examples

Code examples illustrate SQL, PL/SQL, SQL*Plus, or other command-line statements. They are displayed in a monospace (fixed-width) font and separated from normal text as shown in this example:

SELECT username FROM dba_users WHERE username = 'MIGRATE';

The following table describes typographic conventions used in code examples and provides examples of their use.

Convention	Meaning	Example
[ ]	Brackets enclose one or more optional items. Do not enter the brackets.	DECIMAL (digits [ , precision ])
{ }	Braces enclose two or more items, one of which is required. Do not enter the braces.	{ENABLE \| DISABLE}
\|	A vertical bar represents a choice of two or more options within brackets or braces. Enter one of the options. Do not enter the vertical bar.	{ENABLE \| DISABLE} [COMPRESS \| NOCOMPRESS]
`...`	Horizontal ellipsis points indicate either: That we have omitted parts of the code that are not directly related to the example That you can repeat a portion of the code	CREATE TABLE ... AS subquery; SELECT col1, col2, ... , coln FROM employees;
. . .	Vertical ellipsis points indicate that we have omitted several lines of code not directly related to the example.	SQL> SELECT NAME FROM V$DATAFILE; NAME ------------------------------------ /fsl/dbs/tbs_01.dbf /fs1/dbs/tbs_02.dbf . . . /fsl/dbs/tbs_09.dbf 9 rows selected.
Other notation	You must enter symbols other than brackets, braces, vertical bars, and ellipsis points as shown.	acctbal NUMBER(11,2); acct CONSTANT NUMBER(4) := 3;
Italics	Italicized text indicates placeholders or variables for which you must supply particular values.	CONNECT SYSTEM/system_password DB_NAME = database_name
UPPERCASE	Uppercase typeface indicates elements supplied by the system. We show these terms in uppercase in order to distinguish them from terms you define. Unless terms appear in brackets, enter them in the order and with the spelling shown. However, because these terms are not case sensitive, you can enter them in lowercase.	SELECT last_name, employee_id FROM employees; SELECT * FROM USER_TABLES; DROP TABLE hr.employees;
`lowercase`	Lowercase typeface indicates programmatic elements that you supply. For example, lowercase indicates names of tables, columns, or files. Note: Some programmatic elements use a mixture of UPPERCASE and lowercase. Enter these elements as shown.	SELECT last_name, employee_id FROM employees; sqlplus hr/hr CREATE USER mjones IDENTIFIED BY ty3MU9;

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Accessibility of Code Examples in Documentation

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