Lesson 3	Queue propagation
Objective	Work with Queue Propagation.

Work with Queue Propagation

Prior to Oracle, you could queue messages for later retrieval and execution within a single database instance.
The Oracle queue functionality did not work across a database link to a distributed database. Now, with Oracle, you can use Advanced Queuing (AQ) message propagation to enqueue to a remote queue at a remote database. In addition, you can use the scheduling feature to specify the start time and the propagation window. This lesson focus i'ss on the preliminary steps necessary to enable users and a database to use Advanced Queuing.
Review the Slide Show below to see how this works.
Advanced Queuing (AQ): A utility to store transactions in a queue, distribute the queue to other databases, and then retrieve and run the queued transactions.

Preparing to use Advanced Queuing in Oracle

1) The first step in preparing to use advanced queueing is to adjust the parameter of the database

2) You must login as SYS or SYSTEM and grant a privilege to the user

3) After creating a queue, the owner of the queue can allow other users to submit messages to the queue. To do this, the owner of the queue must grant other users these two privileges: (1) The ENQUEUE ANY QUEUE system privilege ( or the ENQUEUE object privilege on a specific queue), and (2) the DEQUEUE ANY QUEUE system privilege (or the DEQUEUE object privilege on a specific queue.)

All the 8.1 privileges needed for working with queues must be granted by an AQ administrator using the DBMS_AQADM.GRANT_SYSTEM_PRIVILEGE package. SYS and SYSTEM are initially given the AQ ADMINISTRATOR role and can grant that role to other users. The AQ_USER_ROLE is only for 8.0 compatible queues. This role is ignored by 8.1 compatible queues. The next lesson discusses connection pooling.

Steps For Setting Up Advanced Queuing

Click the link below to learn more about Advanced Queuing in Oracle.
Steps For Setting Up Advanced Queuing