Advanced Queuing - Oracle

Propagation Questions
Messaging Gateway Questions
manner and either the MGW agent is not running or the agent is running but
unable to perform all necessary clean up action at that time.
The MGW agent tries to remove a DELETE_PENDING subscriber:
1. Each time dbms_mgwadm.remove_subscriber is called and the agent is
running.
2. Each time the MGW agent is started and it finds a DELETE_PENDING
subscriber.
What is the maximum message size for AQ queues with RAW payload?
For AQ queues with RAW payload, the MGW agent can propagate messages of
32512 bytes or less. If the message size is larger than 32512 bytes, an error occurs
when the agent attempts to enqueue or dequeue the message.
Which instance of Oracle Real Application Clusters is used for the
Messaging Gateway agent?
The DBMS_MGWADM.STARTUP procedure submits a job queue job that starts the
MGW agent external process when the job is executed. The instance and force can
be used to control the job and instance affinity. By default the job is set up so that it
can be run by any instance.
How can I control when message propagation occurs?
The MGW agent propagates messages when a propagation subscriber and schedule
are configured for the same source queue, destination queue, and propagation type.
You can control when propagation occurs by using dbms_mgwadm.enable_
propagation_schedule and dbms_mgwadm.disable_propagation_
schedule. By default, the propagation schedule is enabled when it is first created.
To create a propagation job that is initially disabled, call the following APIs in the
indicated order:
1. dbms_mgwadm.schedule_propagation
2. dbms_mgwadm.disable_propagation_schedule
3. dbms_mgwadm.add_subscriber
In release 9.2, the propagation schedule window parameters are not used.
Frequently Asked Questions 6-11