Preface

Oracle9i Streams describes the features and functionality of Streams. This document contains conceptual information about Streams, along with information about configuring and managing a Streams environment. In addition, this document contains detailed examples for configuring a Streams messaging environment, a Streams replication environment, and a rule-based application.

This preface contains these topics:

Audience

Oracle9i Streams is intended for database administrators who create and maintain Streams environments. These administrators perform one or more of the following tasks:

Plan for a Streams environment
Configure a Streams environment
Configure conflict resolution in a Streams environment
Administer a Streams environment
Monitor a Streams environment
Perform necessary troubleshooting activities

To use this document, you need to be familiar with relational database concepts, SQL, distributed database administration, Advanced Queuing concepts, PL/SQL, and the operating systems under which you run a Streams environment.

Organization

This document contains:

Part I, Streams Concepts

Contains chapters that describe conceptual information relating to Streams.

Chapter 1, "Introduction to Streams"

Introduces the major features of Streams and how they can be used.

Chapter 2, "Streams Capture Process"

Contains conceptual information about the Streams capture process. Includes information about logical change records (LCRs), datatypes and types of changes captured, and supplemental logging, along with information about capture process architecture.

Chapter 3, "Streams Staging and Propagation"

Contains conceptual information about staging and propagation in a Streams environment. Includes information about the differences between captured and user-enqueued events, propagation, the differences between transactional and non-transactional queues, and using SYS.AnyData queues. Also includes information about queue and propagation architecture.

Chapter 4, "Streams Apply Process"

Contains conceptual information about the Streams apply process. Includes information about event processing with an apply process, considerations for apply changes to tables, conditions for applying DDL changes, and controlling a trigger's firing property, along with information about the oldest SCN for an apply process and apply process architecture.

Chapter 5, "Rules"

Contains conceptual information about rules. Includes information about rule components, rule sets, and privileges related to rules.

Chapter 6, "How Rules Are Used In Streams"

Contains conceptual information about how rules are used in Streams. Includes information about table-level rules, subset rules, schema-level rules, and global-level rules. Also includes information about rule-based transformations.

Chapter 7, "Streams Conflict Resolution"

Contains conceptual information about conflicts. Includes information about the possible types of conflicts, conflict detection, conflict avoidance, and conflict resolution in Streams environments.

Chapter 8, "Streams Tags"

Contains conceptual information about Streams tags. Includes information about how tag values are used in rules, how a tag value can be set for an apply process, and how to avoid change cycling using tags.

Chapter 9, "Streams Heterogeneous Information Sharing"

Contains conceptual information about heterogeneous information sharing using Streams. Includes information about sharing information in an Oracle database with a non-Oracle database, sharing information in a non-Oracle database with an Oracle database, and using Streams to share information between two non-Oracle databases.

Chapter 10, "Streams High Availability Environments"

Contains conceptual information about using Streams for high availability environments.

Part II, Streams Administration

Contains chapters that describe managing a capture process, staging, propagation, an apply process, rules, rule-based transformations, logical change records (LCRs), and Streams tags.

Chapter 11, "Configuring a Streams Environment"

Contains information about preparing for a Streams environment. Includes instructions for configuring a Streams administrator, setting initialization parameters that are important to Streams, preparing for a capture process, and configuring networking connectivity.

Chapter 12, "Managing a Capture Process"

Contains information about managing a capture process. Includes instructions for creating, starting, stopping, and altering a capture process, as well as other information related to capture process administration.

Chapter 13, "Managing Staging and Propagation"

Contains information about managing staging and propagation of events in a Streams environment. Includes instructions for creating a Streams queue, and instructions for enabling, disabling, and altering a propagation, as well as other information related to staging, propagation, and messaging.

Chapter 14, "Managing an Apply Process"

Contains information about managing an apply process. Includes instructions for creating, starting, stopping, and altering an apply process, as well as instructions about using apply process handlers, configuring conflict resolution, and managing an exception queue.

Chapter 15, "Managing Rules and Rule-Based Transformations"

Contains information about managing rules and rule-based transformations. Includes instructions for managing rules and rule sets, as well as information about granting and revoking privileges related to rules. In addition, this chapter includes instructions for creating, altering, and removing rule-based transformations.

Chapter 16, "Other Streams Management Tasks"

Contains information about managing logical change records (LCRs) and Streams tags. Includes instructions for constructing and enqueuing LCRs, and instructions for setting and removing tag values for a session or an apply process.

Chapter 17, "Monitoring a Streams Environment"

Contains information about using data dictionary views and scripts to monitor a Streams environment. Includes information about monitoring capture processes, queues, propagations, apply processes, rules, rule-based transformations, and tags.

Chapter 18, "Troubleshooting a Streams Environment"

Contains information about possible problems in a Streams environment and how to resolve them. Includes information about troubleshooting a capture process, propagation, apply process, and Streams rules, as well as information about checking trace files and the alert log for problems.

Part III, Example Environments and Applications

Contains chapters that illustrate example environments.

Chapter 19, "Streams Messaging Example"

Contains a step by step example that configures a messaging environment using Streams.

Chapter 20, "Single Database Capture and Apply Example"

Contains a step by step example that configures a single database capture and apply example using Streams. Specifically, this chapter illustrates an example of a single database that captures changes to a table, uses a DML handler during apply to re-enqueue the captured changes into a queue, and then applies a subset of the changes to a different table.

Chapter 21, "Simple Single Source Replication Example"

Contains a step by step example that configures a simple single source replication environment using Streams.

Chapter 22, "Single Source Heterogeneous Replication Example"

Contains a step by step example that configures a single source heterogeneous replication environment using Streams. Also contains step by step examples for adding objects and databases to this environment.

Chapter 23, "Multiple Source Replication Example"

Contains a step by step example that configures a multiple source replication environment using Streams.

Chapter 24, "Rule-Based Application Example"

Contains step by step examples that illustrate a rule-based application that uses the Oracle rules engine.

Appendixes

Contains one appendix that describes the XML schema for logical change records (LCRs).

Appendix A, "XML Schema for LCRs"

Contains the definition of the XML schema for LCRs.

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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