WebSphere MQ function messages
WebSphere® MQ provides the message transport. The messages define what is sent. Information is passed between communicating applications by using messages.
Messages consist of attributes and data:
- The message attributes identify the message and its properties. The message interface uses the attributes and the information in the policy to interpret and construct WebSphere MQ headers and message descriptors. Attributes are properties of the message object. An application can set the attributes before sending a message or access the attributes after receiving a message. The attributes can be defined in a policy that is created by the system administrator.
- The message data is carried in the message. The size of the message can be VARCHAR(32000) or CLOB(1 MB) depending on the function name or the data type that is provided as the function parameter.
Examples of message attributes
The following list contains message attribute examples:
- MessageID
- An identifier for the message. It is usually unique, and typically it is generated by WebSphere MQ acting as the message transport.
- CorrelID
- A correlation identifier that can be used as a key to correlate a response message to a request message.
- Format
- The structure of the message.
- Topic
- Indicates the content of the message for publish or subscribe applications.