Which component of the Push Notifications feature stores the messages that are ready to be sent?

The APEX Push Notifications architecture uses a queue to manage outgoing messages. When a notification is triggered via the APEXPWA API, it is first placed into a queue (the APEXAPPLPUSHNOTIFICATIONS table). A background database job periodically processes this queue, dequeuing messages and sending them to the appropriate third-party push notification service for delivery to the end-user's device. This queuing mechanism ensures reliable and asynchronous delivery of notifications without blocking the main application thread.

B. Application: The application is the source that generates the notification request, but it does not store the messages that are pending delivery.
C. Subscription: A subscription stores the unique endpoint information for a user's device, which is necessary for delivery, but it does not store the message content itself.

- Oracle APEX App Builder User's Guide, 23.2, Section 15.10, "About Push Notifications". The documentation states, "When you call APEXPWA.SENDPUSHNOTIFICATION, APEX enqueues a push notification in the APEXAPPLPUSHNOTIFICATIONS table. A background job (ORACLEAPEXPUSHNOTIFICATIONS) dequeues the push notification and sends it to the push service."