Preface

This manual provides information about Oracle9i's data warehousing capabilities.

This preface contains these topics:

• Audience

• Organization

• Related Documentation

• Conventions

• Documentation Accessibility

Audience

Oracle9i Data Warehousing Guide is intended for database administrators, system administrators, and database application developers who perform the following tasks:

• design, maintain, and use data warehouses.

To use this document, you need to be familiar with relational database concepts, basic Oracle server concepts, and the operating system environment under which you are running Oracle.

Organization

This document contains:

Chapter 1, Data Warehousing Concepts

This chapter contains an overview of data warehousing concepts.

Chapter 2, Logical Design in Data Warehouses

This chapter discusses the logical design of a data warehouse.

Chapter 3, Physical Design in Data Warehouses

This chapter discusses the physical design of a data warehouse.

Chapter 4, Hardware and I/O Considerations in Data Warehouses

This chapter describes some hardware and input-output issues.

Chapter 5, Parallelism and Partitioning in Data Warehouses

This chapter describes the basics of parallelism and partitioning in data warehouses.

Chapter 6, Indexes

This chapter describes how to use indexes in data warehouses.

Chapter 7, Integrity Constraints

This chapter describes some issues involving constraints.

Chapter 8, Materialized Views

This chapter describes how to use materialized views in data warehouses.

Chapter 9, Dimensions

This chapter describes how to use dimensions in data warehouses.

Chapter 10, Overview of Extraction, Transformation, and Loading

This chapter is an overview of the ETL process.

Chapter 11, Extraction in Data Warehouses

This chapter describes extraction issues.

Chapter 12, Transportation in Data Warehouses

This chapter describes transporting data in data warehouses.

Chapter 13, Loading and Transformation

This chapter describes transforming data in data warehouses.

Chapter 14, Maintaining the Data Warehouse

This chapter describes how to refresh in a data warehousing environment.

Chapter 16, Summary Advisor

This chapter describes how to use the Summary Advisor utility.

Chapter 17, Schema Modeling Techniques

This chapter describes the schemas useful in data warehousing environments.

Chapter 18, SQL for Aggregation in Data Warehouses

This chapter explains how to use SQL aggregation in data warehouses.

Chapter 19, SQL for Analysis in Data Warehouses

This chapter explains how to use analytic functions in data warehouses.

Chapter 20, Advanced Analytic Services

This chapter describes using analytic services in combination with Oracle9i.

Chapter 21, Using Parallel Execution

This chapter describes how to tune data warehouses using parallel execution.

Chapter 22, Query Rewrite

This chapter describes how to use Query Rewrite.

Appendix A, "Glossary"

This chapter defines commonly used data warehousing terms.

Appendix B, "Sample Data Warehousing Schema"

This chapter details the schema used throughout much of the book.

Related Documentation

For more information, see these Oracle resources:

• Oracle9i Database Performance Guide and Reference

Many of the examples in this book use the sample schemas of the seed database, which is installed by default when you install Oracle. Refer to Oracle9i Sample Schemas for information on how these schemas were created and how you can use them yourself.

In North America, printed documentation is available for sale in the Oracle Store at

http://oraclestore.oracle.com/

Customers in Europe, the Middle East, and Africa (EMEA) can purchase documentation from

http://www.oraclebookshop.com/

Other customers can contact their Oracle representative to purchase printed documentation.

To download free release notes, installation documentation, white papers, or other collateral, please visit the Oracle Technology Network (OTN). You must register online before using OTN; registration is free and can be done at

http://technet.oracle.com/membership/index.htm

If you already have a username and password for OTN, then you can go directly to the documentation section of the OTN Web site at

http://technet.oracle.com/docs/index.htm

For additional information, see:

• The Data Warehouse Toolkit by Ralph Kimball (John Wiley and Sons, 1996)

• Building the Data Warehouse by William Inmon (John Wiley and Sons, 1996)

Conventions

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

• Conventions in Text

• Conventions in Code Examples

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 monospace (fixed-width font) italic	Lowercase monospace italic font represents placeholders or variables.	You can specify the parallel_clause. Run Uold_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.
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;

Documentation Accessibility

Oracle's goal is to make our products, services, and supporting documentation accessible to the disabled community with good usability. To that end, our documentation includes features that make information available to users of assistive technology. This documentation is available in HTML format, and contains markup to facilitate access by the disabled community. Standards will continue to evolve over time, and Oracle is actively engaged with other market-leading technology vendors to address technical obstacles so that our documentation can be accessible to all of our customers. For additional information, visit the Oracle Accessibility Program Web site at

http://www.oracle.com/accessibility/

JAWS, a Windows screen reader, may not always correctly read the code examples in this document. The conventions for writing code require that closing braces should appear on an otherwise empty line; however, JAWS may not always read a line of text that consists solely of a bracket or brace.