AWS Certified Developer – Associate — Question 46

A developer manages an application that interacts with Amazon RDS. After observing slow performance with read queries, the developer implements Amazon
ElastiCache to update the cache immediately following the primary database update.
What will be the result of this approach to caching?

Answer options

• A. Caching will increase the load on the database instance because the cache is updated for every database update.
• B. Caching will slow performance of the read queries because the cache is updated when the cache cannot find the requested data.
• C. The cache will become large and expensive because the infrequently requested data is also written to the cache.
• D. Overhead will be added to the initial response time because the cache is updated only after a cache miss.

Correct answer: C

Explanation

Option C is correct because continuously updating the cache with infrequently accessed data can lead to excessive storage use and costs. Option A is incorrect as the update frequency does not necessarily increase load on the database, while Option B misunderstands the caching mechanism by misattributing read performance issues. Option D incorrectly suggests that cache misses are the only time the cache is updated, ignoring the immediate updates following database changes.