AWS Certified Solutions Architect – Associate (SAA-C03) — Question 461

A company hosts a three-tier web application in the AWS Cloud. A Multi-AZAmazon RDS for MySQL server forms the database layer Amazon ElastiCache forms the cache layer. The company wants a caching strategy that adds or updates data in the cache when a customer adds an item to the database. The data in the cache must always match the data in the database.

Which solution will meet these requirements?

Answer options

• A. Implement the lazy loading caching strategy
• B. Implement the write-through caching strategy
• C. Implement the adding TTL caching strategy
• D. Implement the AWS AppConfig caching strategy

Correct answer: B

Explanation

The write-through caching strategy ensures that data is written to both the cache and the database at the same time, maintaining real-time data consistency and preventing stale data. In contrast, lazy loading only populates the cache on a cache miss, which does not guarantee immediate updates when database writes occur. Adding a TTL merely expires data over time rather than proactively updating it, and AWS AppConfig is not a database caching solution.