SCHEDULE_PROPAGATION Procedure

This procedure schedules propagation of messages from a queue to a destination identified by a specific dblink.

Messages may also be propagated to other queues in the same database by specifying a NULL destination. If a message has multiple recipients at the same destination in either the same or different queues, then the message is propagated to all of them at the same time.

Syntax

DBMS_AQADM.SCHEDULE_PROPAGATION (
   queue_name      IN    VARCHAR2,
   destination     IN    VARCHAR2 DEFAULT NULL,
   start_time      IN    DATE     DEFAULT SYSDATE,
   duration        IN    NUMBER   DEFAULT NULL,
   next_time       IN    VARCHAR2 DEFAULT NULL,
   latency         IN    NUMBER   DEFAULT 60);

Parameters

Table 5-19 SCHEDULE_PROPAGATION Procedure Parameters

Parameter	Description
queue_name	Name of the source queue whose messages are to be propagated, including the schema name. If the schema name is not specified, then it defaults to the schema name of the administrative user.
destination	Destination dblink. Messages in the source queue for recipients at this destination are propagated. If it is NULL, then the destination is the local database and messages are propagated to other queues in the local database. The length of this field is currently limited to 128 bytes, and if the name is not fully qualified, then the default domain name is used.
start_time	Initial start time for the propagation window for messages from the source queue to the destination.
duration	Duration of the propagation window in seconds. A NULL value means the propagation window is forever or until the propagation is unscheduled.
next_time	Date function to compute the start of the next propagation window from the end of the current window. If this value is NULL, then propagation is stopped at the end of the current window. For example, to start the window at the same time every day, next_time should be specified as 'SYSDATE + 1 - duration/86400'.
latency	Maximum wait, in seconds, in the propagation window for a message to be propagated after it is enqueued. For example: If the latency is 60 seconds, then during the propagation window; if there are no messages to be propagated, then messages from that queue for the destination are not propagated for at least 60 more seconds. It is at least 60 seconds before the queue is checked again for messages to be propagated for the specified destination. If the latency is 600, then the queue is not checked for 10 minutes, and if the latency is 0, then a job queue process will be waiting for messages to be enqueued for the destination. As soon as a message is enqueued, it is propagated.