Each WebSphere MQ message consists of two parts: a header and the application data.
There are five types of header, as shown in the following table
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The message descriptor. Created by the application at message create time. |
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The Transmission Queue header, which contains delivery information in remote queuing. |
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The dead letter header, which identifies conditions that prevent delivery to a destination queue. |
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Reference message header, which contains information to assist in delivery of reference messages. |
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Information header (MQIIH), which is carried with the message using the IMS hierarchical database bridge facility. |
Let's look at the MQMD
header in more detail. The following figure shows how the MQMD
is made up:
The following table shows the meaning of each MQMD
entry in the preceding figure:
|
The queue name for reply messages. |
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If we cannot deliver this message, put it in the DLQ or discard (DLQ is the default). |
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Is the... |