AWS Certified Developer – Associate (DVA-C02) — Question 412

A company has an application that uses an AWS Lambda function to consume messages from an Amazon Simple Queue Service (Amazon SQS) queue. The SQS queue is configured with a dead-letter queue. Due to a defect in the application, AWS Lambda failed to process some messages. A developer fixed the bug and wants to process the failed messages again.

How should the developer resolve this issue?

Answer options

• A. Use the SendMessageBatch API to send messages from the dead-letter queue to the original SQS queue.
• B. Use the ChangeMessageVisibility API to configure messages in the dead-letter queue to be visible in the original SQS queue.
• C. Use the StartMessageMoveTask API to move messages from the dead-letter queue to the original SQS queue.
• D. Use the PurgeQueue API to remove messages from the dead-letter queue and return the messages to the original SQS queue.

Correct answer: C

Explanation

The StartMessageMoveTask API is the standard programmatic method to initiate a dead-letter queue (DLQ) redrive, which automatically moves messages from a DLQ back to their source SQS queue. Other options like SendMessageBatch would require custom code to read and rewrite messages, while ChangeMessageVisibility only alters visibility timeouts within the same queue. The PurgeQueue API permanently deletes messages from a queue rather than transferring them.