In computing, Oracle Advanced Queuing (AQ) is a sort of message-oriented middleware developed by Oracle Corporation and integrated into its Oracle database.
Computing is any activity that uses computers. It includes developing hardware and software, and using computers to manage, process, and communicate information for various purposes. Computing is a critically important, integral component of modern industrial technology. Major computing disciplines include computer engineering, software engineering, computer science, information systems, and information technology.
Message-oriented middleware (MOM) is software or hardware infrastructure supporting sending and receiving messages between distributed systems. MOM allows application modules to be distributed over heterogeneous platforms and reduces the complexity of developing applications that span multiple operating systems and network protocols. The middleware creates a distributed communications layer that insulates the application developer from the details of the various operating systems and network interfaces. APIs that extend across diverse platforms and networks are typically provided by MOM.
Oracle Corporation is an American multinational computer technology corporation headquartered in Redwood Shores, California. The company sells database software and technology, cloud engineered systems, and enterprise software products—particularly its own brands of database management systems. In 2018, Oracle was the third-largest software company by revenue.
AQ uses database structures as a repository for asynchronous queuing as an element in various Oracle-oriented and heterogeneous operations. Oracle features utilising Advanced Queuing include:
In Oracle Data Guard primary databases the queue monitor process (often running as qmn0) interacts with AQ.
The software which Oracle Corporation markets as Oracle Data Guard forms an extension to the Oracle relational database management system (RDBMS). It aids in establishing and maintaining secondary standby databases as alternative/supplementary repositories to production primary databases.
As of Oracle release 9.2, AQ comes bundled with Standard Edition and Enterprise Edition at no extra cost.
As of Oracle release 10.1, AQ is integrated into Oracle Streams, and is called "Oracle Streams AQ".
In computing, the Oracle Streams product from Oracle Corporation encourages users of Oracle databases to propagate information within and between databases. It provides tools to capture, process ('stage') and manage database events via Advanced Queuing queues.
As of Oracle release 12.1, Oracle Streams is deprecated [1] and AQ is again named just "Oracle AQ".
Oracle AQ is used as the internal Java Message Service provider in the Oracle Enterprise Service Bus. In addition to asynchronous message exchanges (point-to-point and publish–subscribe), Oracle AQ can also perform message transformation via SQL functions.
The Java Message Service (JMS) API is a Java message-oriented middleware API for sending messages between two or more clients. It is an implementation to handle the producer–consumer problem. JMS is a part of the Java Platform, Enterprise Edition, and was defined by a specification developed at Sun Microsystems, but which has since been guided by the Java Community Process. It is a messaging standard that allows application components based on Java EE to create, send, receive, and read messages. It allows the communication between different components of a distributed application to be loosely coupled, reliable, and asynchronous.
Oracle Enterprise Service Bus, a fundamental component of Oracle's Services-Oriented Architecture suite of products, provides integration of data and enterprise applications within an organisation and their connected enterprises.
In software architecture, publish–subscribe is a messaging pattern where senders of messages, called publishers, do not program the messages to be sent directly to specific receivers, called subscribers, but instead categorize published messages into classes without knowledge of which subscribers, if any, there may be. Similarly, subscribers express interest in one or more classes and only receive messages that are of interest, without knowledge of which publishers, if any, there are.
Oracle AQ is available in all editions of Oracle database, including XE.
