Which actions should the developer take to increase the resiliency of the application when the batch response includes values in UnprocessedKeys?

A developer has an application that makes batch requests directly to Amazon DynamoDB by using the BatchGetItem low-level API operation. The responses frequently return values in the UnprocessedKeys element.

Which actions should the developer take to increase the resiliency of the application when the batch response includes values in UnprocessedKeys? (Choose two.)
A . Retry the batch operation immediately.
B . Retry the batch operation with exponential backoff and randomized delay.
C . Update the application to use an AWS software development kit (AWS SDK) to make the requests.
D . Increase the provisioned read capacity of the DynamoDB tables that the operation accesses.
E . Increase the provisioned write capacity of the DynamoDB tables that the operation accesses.

View Answer

Answer: B, C

Explanation:

The UnprocessedKeys element indicates that the BatchGetItem operation did not process all of the requested items in the current response. This can happen if the response size limit is exceeded or if the table’s provisioned throughput is exceeded. To handle this situation, the developer should retry the batch operation with exponential backoff and randomized delay to avoid throttling errors and

reduce the load on the table. The developer should also use an AWS SDK to make the requests, as the SDKs automatically retry requests that return UnprocessedKeys.

Reference: [BatchGetItem – Amazon DynamoDB]

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