Advanced Queuing - Oracle

Listening to One or More Multiconsumer Queues
Examples
See Chapter 3, "AQ Programmatic Environments" for a list of available functions in
each programmatic environment. Examples in the following programmatic
environments are provided:
PL/SQL (DBMS_AQ Package): Listen to Queues on page 11-37
C (OCI): Listen to Multiconsumer Queues on page 11-38
PL/SQL(DBMS_AQPackage):ListentoQueues
/* The listen call allows you to monitor a list of queues for messages for
specific agents. You need to have dequeue privileges for all the queues
you wish to monitor. */
Listen to Multiconsumer Queue (Timeout of Zero).
DECLARE
Agent_w_msg aq$_agent;
My_agent_list dbms_aq.agent_list_t;
BEGIN
/* NOTE: MCQ1, MCQ2, MCQ3 are multiconsumer queues in SCOTT’s schema
* SCQ1, SCQ2, SCQ3 are single-consumer queues in SCOTT’s schema
*/
Qlist(1):= aq$_agent('agent1', 'MCQ1', NULL);
Qlist(2):= aq$_agent('agent2', 'scott.MCQ2', NULL);
Qlist(3):= aq$_agent('agent3', 'scott.MCQ3', NULL);
/* Listen with a time-out of zero: */
DBMS_AQ.LISTEN(
agent_list => My_agent_list,
wait => 0,
agent => agent_w_msg);
DBMS_OUTPUT.PUT_LINE('Message in Queue :- ' || agent_w_msg.address);
DBMS_OUTPUT.PUT_LINE('');
END;
/
Listen to Mixture of Multiconsumer Queues (Timeout 100 Seconds).
DECLARE
Agent_w_msg aq$_agent;
My_agent_list dbms_aq.agent_list_t;
BEGIN
Operational Interface: Basic Operations 11-37