aws logoAmazon continues to expand the services and infrastructure it provides online. Early this morning, it announced that you can run a powerful database in Amazon’s cloud with its Relational Database Service (RDS).

The RDS should serve as an online alternative to buying and maintaining a database server such as those offered by Sun (which owns database company mySQL). The new service uses mySQL technology, so Amazon says it should be easy for developers to make the switch.

This isn’t Amazon’s first database product, but it moves Amazon further in the direction of supporting complex applications that store important business data. Here’s how Amazon describes the difference between the new RDS and its other services like Amazon SimpleDB or running a database in its Elastic Compute Cloud:

Amazon RDS enables you to run a fully featured relational database while offloading database administration; Amazon SimpleDB provides simple index and query capabilities with seamless scalability; and using one of our many relational database AMIs on Amazon EC2 and Amazon EBS allows you to operate your own relational database in the cloud.

Also, as noted by Krishnan Subramanian at CloudAve, this news could be trouble for FathomDB, a startup that helps customers run databases on Amazon infrastructure. As Amazon expands its database serices, FathomDB’s might become redundant.