Amazon Relational Database Service or Amazon RDS is a distributed relational database service by Amazon.com

Amazon.com

Amazon.com, Inc. is a multinational electronic commerce company headquartered in Seattle, Washington, United States. It is the world's largest online retailer. Amazon has separate websites for the following countries: United States, Canada, United Kingdom, Germany, France, Italy, Spain, Japan, and...

. It is a web service running "in the cloud"

Cloud computing

Cloud computing is the delivery of computing as a service rather than a product, whereby shared resources, software, and information are provided to computers and other devices as a utility over a network ....

 and provides users a relational database for use in their applications. Amazon RDS makes it easy to set up, operate, and scale a relational database. Complex administration processes like patching the database software, backing up your database and enabling point in time recovery are managed automatically. Scaling storage and compute resources can be performed by a single API call. Amazon RDS was first released on 22 October 2009 supporting Informix databases

. In June 2011, Oracle database

Oracle database

The Oracle Database is an object-relational database management system produced and marketed by Oracle Corporation....

support was added.

Features

Amazon RDS is simple to use. A new DB instance can be launched from the AWS Management Console or using the Amazon RDS APIs. Monitoring the compute and storage resource utilization of your DB Instance is easy. These performance metrics are available using the AWS Management Console or Amazon CloudWatch APIs.
Amazon RDS offers many different features to support different use cases. Some of the major features are:

Multi AZ deployment

Multi-Availability Zone deployments are targeted for production environments . Multi-AZ deployments provide enhanced availability and data durability for MySQL instances. When you create or modify your DB Instance to run as a Multi-AZ deployment, Amazon RDS automatically provisions and maintains a synchronous “standby” replica in a different Availability Zone (independent infrastructure in a physically separate location). In the event of planned database maintenance or unplanned service disruption, Amazon RDS automatically failsover to the up-to-date standby ensuring that database operations resume quickly without administrative intervention.

Read Replicas

Read Replicas make it easy to take advantage of MySQL’s native, asynchronous replication functionality. Read Replicas help in scaling out beyond the capacity constraints of a single DB Instance for read-heavy database workloads. They can also be used for serving read traffic when the primary database is unavailable.

Reserved Instances

Amazon RDS DB instances come in two packages: On-Demand DB Instances and Reserved DB Instances. The two instance types are exactly the same except for their billing. On-Demand instances are billed at an ongoing hourly usage rate. Reserved DB Instances require a low, up-front, one-time fee and in turn provide a significant discount on the hourly usage charge for that instance. Thus Reserved DB Instances enable you to take advantage of the rich functionality of Amazon RDS at lower cost and can provide substantial savings over owning database assets or running only On-Demand DB instances.

Database Instance Types

Amazon RDS currently supports six DB Instance Classes, to support different types of workloads :

Small DB Instance :1.7 GB memory, 1 ECU (1 virtual core with 1 ECU), 64-bit platform, Moderate I/O Capacity
Large DB Instance :7.5 GB memory, 4 ECUs (2 virtual cores with 2 ECUs each), 64-bit platform, High I/O Capacity
Extra Large DB Instance :15 GB of memory, 8 ECUs (4 virtual cores with 2 ECUs each), 64-bit platform, High I/O Capacity (MySQL DB Engine Only)
High-Memory Extra Large Instance :17.1 GB memory, 6.5 ECU (2 virtual cores with 3.25 ECUs each), 64-bit platform, High I/O Capacity
High-Memory Double Extra Large DB Instance :34 GB of memory, 13 ECUs (4 virtual cores with 3,25 ECUs each), 64-bit platform, High I/O Capacity
High-Memory Quadruple Extra Large DB Instance :68 GB of memory, 26 ECUs (8 virtual cores with 3.25 ECUs each), 64-bit platform, High I/O Capacity