Notification Directives

A notification directive lets you journal committed changes made to a table or JSON-relational duality view and query those changes efficiently.

The history of changes is stored in a notification table and exposed through a notification view. Applications can query the notification view to maintain object caches, replicate application objects, or generate change events for downstream services.

Notification directives can be created on:

• Tables: The database logs the new values of the selected table columns and, optionally, key columns, old values, and SYS_CONTEXT values.
• JSON-relational duality views: Oracle logs the columns ID and DATA of the duality view, and optional SYS_CONTEXT values. The ID column contains the object’s _id value.

Notification directives can track INSERT, UPDATE, DELETE, or a combination of these three operation types.

Notification rows are visible only after the transaction commits. For table notifications, the notification history includes intermediate row versions produced by a transaction. For notifications on JSON-relational duality views, Oracle logs only the final committed object for each affected object.

Related Topics

• Creating Notification Directives
• Creating Notification Directives on Tables
• Creating Notification Directives on JSON-Relational Duality Views
• Altering or Dropping an Existing Notification Directive
• Purging Notification History
• Data Dictionary Views for Listing Notification Directives