AWS Certified Solutions Architect Professional SAP-C02 Practice Question

The correct solution is to migrate the shopping cart and user session data to Amazon DynamoDB. DynamoDB is a purpose-built NoSQL key-value database designed for high-traffic, low-latency workloads, which is a perfect fit for shopping cart and session data access patterns. This approach decouples the high-volume, volatile data from the core relational database, directly addressing the performance bottleneck. DynamoDB offers seamless, automatic scaling to handle traffic spikes and provides single-digit millisecond latency. The use of DynamoDB Time to Live (TTL) is an efficient, no-cost mechanism to automatically delete expired session data, reducing storage costs and eliminating the need for custom cleanup logic.

• Migrating the entire database to Amazon Aurora PostgreSQL is a plausible but less optimal solution. While Aurora would reduce management overhead compared to a self-managed cluster, it is still a relational database. It would not fully resolve the underlying issue of using a relational model for a high-concurrency, key-value workload, where lock contention could still occur at extreme scale.

• Using Amazon ElastiCache for Redis is a strong option for caching and session state, but it is less ideal for shopping cart data where durability is critical. ElastiCache is an in-memory service and is not persistent by default. While Redis can be configured for persistence, DynamoDB provides stronger, built-in durability by automatically replicating data across multiple Availability Zones, making it a more reliable choice for data that cannot be lost, such as a customer's shopping cart.

• Deploying Amazon DynamoDB Accelerator (DAX) in front of the PostgreSQL database is incorrect because DAX is an in-memory cache designed exclusively for Amazon DynamoDB. It is not compatible with other database engines like PostgreSQL. This option demonstrates a misunderstanding of the service's function.