IBM GC34-5557-00 User Manual
What is a Queue?
A queue is a data structure that stores messages. The messages may be put on
the queue by applications or by a queue manager as part of its normal
operation.
the queue by applications or by a queue manager as part of its normal
operation.
Queues exist independently of the applications that use them. A queue can
exist in main storage (if it is temporary), on disk or similar auxiliary storage
(if it must be kept in case of recovery), or in both places (if it is currently
being used, and must also be kept for recovery). Each queue belongs to a
queue manager, which is responsible for maintaining it. The queue manager
puts the messages it receives onto the appropriate queue.
exist in main storage (if it is temporary), on disk or similar auxiliary storage
(if it must be kept in case of recovery), or in both places (if it is currently
being used, and must also be kept for recovery). Each queue belongs to a
queue manager, which is responsible for maintaining it. The queue manager
puts the messages it receives onto the appropriate queue.
Queues can exist either in your local system, in which case they are called
local queues, or at another queue manager, in which case they are called remote
queues.
local queues, or at another queue manager, in which case they are called remote
queues.
Applications use MQI calls to send and receive messages. One application can
put a message on a queue and another application can retrieve the message
from the same queue.
put a message on a queue and another application can retrieve the message
from the same queue.
MQSeries Objects
An MQSeries object is a recoverable resource that is managed by MQSeries.
Many of the tasks that are described in this chapter involve manipulating the
following types of MQSeries object:
v Queue managers
v Queues
v Process definitions
v Channels
v Namelists
Many of the tasks that are described in this chapter involve manipulating the
following types of MQSeries object:
v Queue managers
v Queues
v Process definitions
v Channels
v Namelists
MQSeries creates default objects for you when you create a queue manager.
Each object has a name associated with it. You can specify that name in
MQSeries commands and MQI calls to refer to the object. Names must be
unique within each of the object types. For example, you can have a queue
and a process with the same name, but you cannot have two queues with the
same name.
MQSeries commands and MQI calls to refer to the object. Names must be
unique within each of the object types. For example, you can have a queue
and a process with the same name, but you cannot have two queues with the
same name.
Messages and Queues
Chapter 1. About MQSeries
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