SAP-C02 Continuous Improvement for Existing Solutions Practice Question

A company uses Amazon RDS for MySQL for its database. The operations team notices that read queries are slow during peak hours. The application is read-heavy and can tolerate eventual consistency. Which solution would improve read performance with minimal application changes?

⚠ Common exam trap

SAP-C02 often tests the misconception that Multi-AZ improves read performance (it does not; the standby is not readable) or that RDS Proxy increases read throughput (it pools connections, not reads).

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Create an RDS read replica and direct read traffic to it.

Creating an RDS read replica and directing read traffic to it offloads read queries from the primary instance, improving read performance for a read-heavy application that tolerates eventual consistency. This requires minimal application changes—typically just updating the connection string for read operations to point to the replica endpoint. Read replicas use asynchronous replication, so they are suitable for eventually consistent reads.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
Increase the DB instance class to a larger size.
Why it's wrong here
Scaling the DB instance vertically raises compute and memory for all workloads but leaves a single endpoint serving every read, so peak read throughput remains constrained and cost rises continuously. Read replicas offload read traffic across multiple endpoints, matching the read-heavy, eventually consistent requirement. Vertical scaling suits write-bound or CPU-bound databases.
✗
Enable Multi-AZ deployment for failover support.
Why it's wrong here
Multi-AZ maintains a synchronous standby for failover, and that standby does not serve read traffic, so it adds availability without relieving peak read load. Read replicas distribute read queries across additional endpoints, which fits the read-heavy, eventually consistent workload. Multi-AZ is correct when the priority is resilience to an Availability Zone failure.
✗
Enable RDS Proxy to pool database connections.
Why it's wrong here
RDS Proxy pools and reuses connections, which cuts the overhead of opening new ones; it does not add read capacity or route read queries elsewhere. It is tempting because it genuinely helps with connection exhaustion under high concurrency, but the stem's slow reads during peak load require offloading queries to replicas.
✓
Create an RDS read replica and direct read traffic to it.
Why this is correct
An RDS read replica offloads read queries to a separate MySQL instance via asynchronous replication, directly relieving the primary during peak hours. Because the application tolerates eventual consistency, replication lag is acceptable, and directing reads to the replica endpoint requires minimal application change.

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SAP-C02 Continuous Improvement for Existing Solutions Practice Question

Why each option matters

Option-by-option breakdown

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