This manual provides an architectural and conceptual overview of the Oracle database server, which is an object-relational database management system.

The book describes how the Oracle database server functions, and it lays a conceptual foundation for much of the practical information contained in other manuals. Information in this manual applies to the Oracle database server running on all operating systems.

This preface contains these topics:


Oracle Database Concepts is intended for technical users, primarily database administrators and database application developers, who are new to Oracle Database. Typically, the reader of this manual has had experience managing or developing applications for other relational databases.

To use this manual, you must know the following:

  • Relational database concepts in general

  • Concepts and terminology in Introduction to Oracle Database

  • The operating system environment under which you are running Oracle

Documentation Accessibility

For information about Oracle's commitment to accessibility, visit the Oracle Accessibility Program website at

Access to Oracle Support

Oracle customers that have purchased support have access to electronic support through My Oracle Support. For information, visit or visit if you are hearing impaired.

Related Documentation

For related documentation, see "Oracle Database Documentation Roadmap".

Many publications in the Oracle Database documentation set use the sample schemas of the database that is installed by default when you install Oracle Database. Refer to Oracle Database Sample Schemas for information on how these schemas were created and how you can use them.


The following text conventions are used in this manual:

Convention Meaning


Boldface type indicates graphical user interface elements associated with an action, or terms defined in text or the glossary.


Italic type indicates manual titles, emphasis, or placeholder variables for which you supply particular values.


Monospace type indicates commands within a paragraph, URLs, code in examples, text that appears on the screen, or text that you enter.