Which service provides cost-efficient, resizeable capacity for an industry-standard relational database and manages common database administration tasks?

• A. Amazon DynamoDB
• B. Amazon DocumentDB
• C. Amazon Aurora
• D. Amazon RDS

Answer: (D)

This question tests understanding of a fully managed relational database service that scales and takes care of routine administration. Amazon RDS fits this description. It provides a managed environment for industry-standard relational engines (such as MySQL, PostgreSQL, MariaDB, Oracle, and SQL Server), and you can scale capacity by resizing the DB instance and storage. Storage can grow as needed, and you pay only for what you provision. RDS automates common database administration tasks like backups, patching, monitoring, and maintenance, and it supports high availability with Multi-AZ deployments and read replicas for scaling reads.

DynamoDB is a NoSQL key-value/document database, so it isn’t a relational option. DocumentDB is a MongoDB-compatible document store, not relational. Aurora is also a relational option within AWS and offers high performance, but the general managed relational service that handles typical admin tasks across standard engines is Amazon RDS.