Which DynamoDB table configuration will meet these requirements MOST cost-effectively?

Explanations:

While configuring DynamoDB with provisioned capacity and setting up auto scaling can be effective for predictable workloads, the application’s traffic is described as unpredictable. This means that there may be times when the provisioned capacity is insufficient, leading to throttling and potential performance issues. Auto scaling can mitigate this to some extent, but it may not be as cost-effective for variable traffic patterns compared to on-demand mode.

Configuring DynamoDB in on-demand mode is ideal for unpredictable workloads. It automatically adjusts to accommodate fluctuating traffic patterns without the need for manual capacity management, ensuring that the application can handle moderate to high read and write throughput efficiently. This approach is also cost-effective since you only pay for the actual read and write requests, avoiding costs associated with over-provisioning.

Similar to option A, this option uses provisioned capacity, which may not be suitable for unpredictable workloads. Even though it incorporates auto scaling, it still runs the risk of not adjusting quickly enough to meet sudden increases in traffic, leading to potential throttling. Additionally, the use of the Standard-IA table class is not appropriate here, as it is intended for infrequent access data, which is not aligned with the application’s moderate to high throughput requirements.

While using on-demand mode is suitable for unpredictable workloads, the use of the Standard-IA table class is not appropriate for the expected moderate to high read and write throughput. Standard-IA is designed for data that is accessed less frequently, which does not align with the application’s usage pattern. Therefore, this configuration would not meet the requirements effectively.