We love Microsoft Azure. It is by far the most developed cloud providers in IaaS, PaaS, and even SaaS (Office 365) that you can get. It is well thought out from an administration point of view, a strong API to control most aspects of it, and offers as many developer-oriented services as you can imagine. Much like Amazon, it also offers its variety of databases as a service.
Database as a Service (DBaaS)
Buying a license for database software and installing it on a server is only a small portion of the cost and effort. Since most database licenses are not cheap to begin with, you can imagine the total bill, which includes items such as: