Advanced Queuing - Oracle

Enqueuing and Dequeuing Of Messages
BEGIN
pragma exception_init (no_messages, -25228);
dequeue_options.wait := DBMS_AQ.NO_WAIT;
BEGIN
/* Consumer BLUE will get MESSAGE 2: */
dequeue_options.consumer_name := ’BLUE’;
dequeue_options.navigation := FIRST_MESSAGE;
LOOP
DBMS_AQ.DEQUEUE(queue_name => ’msg_queue_multiple’,
dequeue_options => dequeue_options,
message_properties => message_properties,
payload => message,
msgid => message_handle);
DBMS_OUTPUT.PUT_LINE (’Message: ’ || message.subject ||
’ ... ’ || message.text );
dequeue_options.navigation := NEXT_MESSAGE;
END LOOP;
EXCEPTION
WHEN no_messages THEN
DBMS_OUTPUT.PUT_LINE (’No more messages for BLUE’);
COMMIT;
END;
BEGIN
/* Consumer RED will get MESSAGE 1 and MESSAGE 2: */
dequeue_options.consumer_name := ’RED’;
dequeue_options.navigation := DBMS_AQ.FIRST_MESSAGE
LOOP
DBMS_AQ.DEQUEUE(queue_name => ’msg_queue_multiple’,
dequeue_options => dequeue_options,
message_properties => message_properties,
payload => message,
msgid => message_handle);
DBMS_OUTPUT.PUT_LINE (’Message: ’ || message.subject ||
’ ... ’ || message.text );
dequeue_options.navigation := NEXT_MESSAGE;
END LOOP;
EXCEPTION
A-46 Oracle9i Application Developer’s Guide - Advanced Queuing