These questions are independently created for study purposes. They are not official AWS exam questions, actual exam questions, leaked questions, or exam dumps.
CLF-020
Which of the following is the most appropriate description of Amazon RDS?
Choices
Explanation and answer
Read the explanation and correct answer (spoiler — try answering first)
Correct answer: A. A managed service for using relational databases.
Explanation
Amazon RDS is a managed service for using relational databases such as MySQL, PostgreSQL, MariaDB, Oracle Database, and Microsoft SQL Server.
Per-choice explanations
A. A managed service for using relational databases.
Correct. RDS is a managed service for relational databases.
B. A message queue service.
Incorrect. The message queue is Amazon SQS.
C. A content delivery network.
Incorrect. The CDN is Amazon CloudFront.
D. A NoSQL key-value database service.
Incorrect. NoSQL key-value use cases are served by Amazon DynamoDB.
Practical Use
Amazon RDS (Relational Database Service) is a managed service that provides the setup, operation, and scaling of relational databases (RDB). AWS handles OS patching, database engine upgrades, automatic snapshots (backups), and failover (automatic switchover in a Multi-AZ deployment). The user can focus on data model design, SQL tuning, and application development. The supported engines are six families: Amazon Aurora (MySQL- and PostgreSQL-compatible), MySQL, PostgreSQL, MariaDB, Oracle Database, and Microsoft SQL Server. Aurora is a cloud-native engine that AWS developed in-house, designed to provide higher throughput and lower latency than ordinary MySQL. Compared with installing an RDB on Amazon EC2 yourself, RDS significantly reduces operational overhead, but the trade-off is that you cannot perform OS-level customization. When you enable a Multi-AZ deployment, a standby replica is created in a different Availability Zone, and an automatic failover happens when the primary fails. Creating a Read Replica lets you scale out reads. On CLF-C02, this content is asked as a direct question that requests which managed service is for relational databases. Distractors include Amazon DynamoDB (NoSQL), Amazon CloudFront (CDN), and Amazon SQS (message queue). If you keep the axis that RDS is a managed service for relational databases, you can reliably select the correct answer. From SAA-C03 onward, the differences between Multi-AZ and Read Replicas, the characteristics of Aurora, parameter groups, encryption, and sharing and copying snapshots are explored in depth.