Amazon Relational Database Service

A relational database whose operations are supported by AWS.

A managed service for running relational databases such as MySQL and PostgreSQL. Provides settings such as backups and Multi-AZ.

• Storing order and user data
• Business applications that use SQL
• Applications that require transactions

• Suitable for structured data and SQL
• Use Multi-AZ to improve availability
• Use Read Replicas to scale read performance

• Multi-AZ targets availability; Read Replicas target read performance
• Consider backup retention period and storage costs
• Design subnet groups and Security Groups

Amazon Relational Database Service (Amazon RDS) is a managed relational database service. AWS takes over operational tasks such as OS patching, minor version upgrades of the database engine, automated backups, snapshot creation, and automatic failover during failures, allowing users to focus on schema design, query tuning, and application-side logic. Supported database engines include Amazon Aurora (MySQL/PostgreSQL compatible), MySQL, PostgreSQL, MariaDB, Oracle Database, and Microsoft SQL Server, for a total of six engines. Instance type, storage type, and storage capacity can be chosen to fit the workload, and an option for automatic storage scaling based on usage is also available. Major features for availability and fault tolerance include Multi-AZ deployment (placing a primary and a synchronous standby in different AZs, with automatic failover during failures), read replicas (load balancing for read queries and certain cross-region configurations), point-in-time recovery via automated backups, and manual snapshots for point-in-time preservation. Pricing is based on a combination of DB instance running time multiplied by instance type, storage capacity, backup capacity, and data transfer volume. Long-term commitment discounts via Reserved Instances are also available. In CLF-C02, a frequent topic is the division of responsibilities under the shared responsibility model (who handles patching and backups) when comparing self-managed databases on EC2 with using RDS.

• What is Amazon RDS (AWS Official Documentation)
• Amazon RDS (AWS Official)

Last updated: 2026-06-01