A message flow reads messages from a queue Database Node fails to insert data in the table. If no error handling and rollback is implemented in the message flow, which of the following statements is true?
A . The transaction is by default rolled back in a globally coordinated manner.
B . The message fails the Input Node and cannot be propagated out of the Out terminal. The transaction is rolled back.
C . The error is caught by the MQ Input Node and if the Catch terminal is not connected the message is rolled back into the queue.
D . The message flow rolls back the database transaction but not the MQ transaction unless a XA coordinated transaction is configured.
Answer: C
Explanation:
The MQInput node takes certain actions when handling errors with persistent and transactional messages. The node attempts retry processing when a transactional message is rolled back to the input queue. Non-transactional messages are not rolled back to the input queue when an exception occurs.
If the MQInput node has successfully propagated the message to the out terminal and an exception is thrown in the out flow, the message is returned to the MQInput node:
– If you have not connected the Catch terminal, the message is rolled back to the input queue. The MQInput node writes the error to the local error log and invokes the retry logic, described in Handling retry processing.
– If you have connected the Catch terminal, you are responsible for handling the error in the flow connected to the Catch terminal. The broker creates a new exception list to represent the error and this list is propagated to the Catch terminal as part of the message tree, but neither the MQInput node nor the broker provide any further failure processing.
References: https://www.ibm.com/support/knowledgecenter/SSMKHH_9.0.0/com.ibm.etools.mft.doc/ ac00414_.htm
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