What's New in Oracle Streams AQ?

This section describes new features of the Oracle Database 10g Release 2 (10.2) and provides pointers to additional information. New features information from previous releases is also retained to help those users migrating to the current release.

The following sections describe the new features in Oracle Streams AQ:

New Features in Oracle Streams AQ 10g Release 2 (10.2)

Buffered Messaging

Buffered messaging combines the rich functionality that Oracle Streams AQ has always offered with a much faster queuing implementation. Buffered messaging is faster than persistent messaging, because its messages reside in shared memory. They are usually written to disk only when the total memory consumption of buffered messages approaches the available shared memory limit. Buffered messaging is ideal for applications that do not require the reliability and transaction support of Oracle Streams AQ persistent messaging.

Commit-Time Ordering

Commit-time ordering orders messages by an approximate CSCN calculated for each transaction. It is useful when transactions are interdependent or when browsing the messages in a queue must yield consistent results.

See Also:

Notification Enhancements

Asynchronous notification allows clients to receive notifications of messages of interest. Oracle Streams AQ 10g Release 2 (10.2) provides the following notification enhancements:

Queue-To-Queue Propagation

Oracle Streams AQ 10g Release 2 (10.2) supports queue-to-queue propagation, giving you finer-grained control when propagating messages to several queues.

In a Real Application Clusters (RAC) environment, this enables transparent failover when propagating messages to a destination RAC system. You no longer need to repoint your database links if the owner instance of the target queue fails on RAC.

New Features in Oracle Streams AQ 10g Release 1 (10.1)

Advanced Queuing has been integrated into Oracle Streams, and is now called Oracle Streams AQ. It supports all existing functionality and more, including:

Oracle Messaging Gateway

In this release Oracle Messaging Gateway has the following new functionality:

Deprecated Features

Java AQ API is deprecated in favor of a unified, industry-standard JMS interface. The Java AQ API is still being supported for legacy applications. However, Oracle recommends that you migrate your Java AQ API application to JMS and that new applications use JMS.

Also deprecated in this release are 8.0-style queues. All new functionality and performance improvements are confined to the newer style queues. Oracle recommends that any new queues you create be 8.1-style or newer and that you migrate existing 8.0-style queues at your earliest convenience.