Edition-Based Redefinition (EBR)

Edition-Based Redefinition (EBR) is a feature in Oracle AI Database that enables online application upgrade with uninterrupted availability of the application. When the installation of an upgrade is complete, the pre-upgrade application and the post-upgrade application can be used at the same time. Therefore, an existing session can continue to use the pre-upgrade application until its user decides to end it; and all new sessions can use the post-upgrade application. When there are no longer any sessions using the pre-upgrade application, it can be retired. In this way, EBR allows hot rollover from the pre-upgrade version to the post-upgrade version, with zero downtime.

What's New in Edition-Based Redefinition

Zero Downtime Upgrades with Edition-Based Redefinition

(Overview Video)

Zero-downtime application upgrades with Edition-Based Redefinition (EBR)

(Technical Deep Dive Video)

Demo - Using Edition-Based Redefinition and Online Redefinition with Liquibase and SQLcl

(Demo Video)

Topic	Description
Key Benefits	Minimize Application Downtime - Upgrades the database schema objects of an application while users continue to run the existing version. Isolate Application Changes - Keeps schema upgrade changes separate from the existing application until they are ready to be made available. Validate Before Cutover - Enables the upgraded application to be tested before making it available to all users. Support Phased Upgrades - Allows the upgraded application to be made available to some users while others continue using the previous version. Maintain Data Availability During Upgrades - Allows users of the existing application to continue reading and changing data while supported structural changes are made.
Key Capabilities	Application Versioning - Maintains multiple versions of editionable application objects in the same database. Online Code Changes - Installs and modifies editionable application objects in a new edition without affecting users of the existing edition. Concurrent Application Versions - Allows different sessions to use different editions of an application at the same time. Edition-Specific Data Views - Allows different application editions to see the table representation appropriate for each version. Hot Rollover - Supports simultaneous use of old and new application versions while keeping their different data representations synchronized.
How it Works	Edition-Based Redefinition (EBR) isolates application changes in a new Edition, allowing existing and upgraded versions of an application to coexist during an upgrade. Editions - Isolate different versions of editionable application objects. Editioning Views - Present the table structure appropriate for each application edition. Cross-edition Triggers - Propagate data changes between old and new table representations (Editioning Views) when both versions must remain in use.

Topic

Description

Key Benefits

Minimize Application Downtime - Upgrades the database schema objects of an application while users continue to run the existing version.
Isolate Application Changes - Keeps schema upgrade changes separate from the existing application until they are ready to be made available.
Validate Before Cutover - Enables the upgraded application to be tested before making it available to all users.
Support Phased Upgrades - Allows the upgraded application to be made available to some users while others continue using the previous version.
Maintain Data Availability During Upgrades - Allows users of the existing application to continue reading and changing data while supported structural changes are made.

Key Capabilities

Application Versioning - Maintains multiple versions of editionable application objects in the same database.
Online Code Changes - Installs and modifies editionable application objects in a new edition without affecting users of the existing edition.
Concurrent Application Versions - Allows different sessions to use different editions of an application at the same time.
Edition-Specific Data Views - Allows different application editions to see the table representation appropriate for each version.
Hot Rollover - Supports simultaneous use of old and new application versions while keeping their different data representations synchronized.

How it Works

Edition-Based Redefinition (EBR) isolates application changes in a new Edition, allowing existing and upgraded versions of an application to coexist during an upgrade.

Editions - Isolate different versions of editionable application objects.
Editioning Views - Present the table structure appropriate for each application edition.
Cross-edition Triggers - Propagate data changes between old and new table representations (Editioning Views) when both versions must remain in use.