Advanced Queuing - Oracle

Sender Identification
Enqueue Features
Applications can mark the messages they send with a custom identification. Oracle
also automatically identifies the queue from which a message was dequeued. This
allows applications to track the pathway of a propagated message or a string
messages within the same database.
Time Specification and Scheduling
Rule-Based Subscribers
Asynchronous Notification
Delay interval or expiration intervals can be specified for an enqueued message,
thereby providing windows of execution. A message can be marked as available for
processing only after a specified time elapses (a delay time) and has to be consumed
before a specified time limit expires.
A message can be delivered to multiple recipients based on message properties or
message content. Users define a rule-based subscription for a given queue as the
mechanism to specify interest in receiving messages of interest. Rules can be
specified based on message properties and message data (for object and raw
payloads). Subscriber rules are then used to evaluate recipients for message
delivery.
To see this feature applied in the context of the BooksOnLine scenario, refer to
"Rule-Based Subscription" on page 8-86.
The asynchronous notification feature allows clients to receive notification of a
message of interest. The client can use it to monitor multiple subscriptions. The
client does not have to be connected to the database to receive notifications
regarding its subscriptions.
Clients can use the OCI function, LNOCISubcriptionRegister, or the PL/SQL
procedure DBMS_AQ.REGISTER to register interest in messages in a queue. Refer to
"Registering for Notification" in Chapter 11, "Operational Interface: Basic
Operations" for more information.
To see this feature applied in the context of the BooksOnLine scenario, refer to
"Asynchronous Notifications" on page 8-97.
Introduction to Oracle Advanced Queuing 1-17