AWS Certified Solutions Architect – Associate (SAA-C02) — Question 99

A company has a mobile chat application with a data store based in Amazon DynamoDB. Users would like new messages to be read with as little latency as possible. A solutions architect needs to design an optimal solution that requires minimal application changes.
Which method should the solutions architect select?

Answer options

• A. Configure Amazon DynamoDB Accelerator (DAX) for the new messages table. Update the code to use the DAX endpoint.
• B. Add DynamoDB read replicas to handle the increased read load. Update the application to point to the read endpoint for the read replicas.
• C. Double the number of read capacity units for the new messages table in DynamoDB. Continue to use the existing DynamoDB endpoint.
• D. Add an Amazon ElastiCache for Redis cache to the application stack. Update the application to point to the Redis cache endpoint instead of DynamoDB.

Correct answer: A

Explanation

The correct answer is A because configuring Amazon DynamoDB Accelerator (DAX) provides a fully managed, in-memory cache that can reduce response times for reads, requiring minimal changes to the application. Options B and D involve significant changes to the application's architecture and code, while option C only increases capacity but does not optimize latency as effectively as DAX.