
Amazon SimpleDB
SimpleDB is a NoSQL database that can be defined as a serverless database because it scales automatically, it is highly available without needing to pay for provisions, and you are only billed by the seconds that the database engine needs to execute your queries.
You can use SimpleDB to make queries using a SQL-like syntax, but SimpleDB is very limited in terms of functionalities. It's so limited that it only stores string fields! If you store a datetime data type, you need to save it as a string ISO representation to avoid localization issues and to be able to make the where clauses. If you want to store numbers, use zero-padding. And how can we make where clauses with negative numbers? It is done by adding a large offset to all numbers to avoid storing negatives! As you can see, building a system on top of SimpleDB can be hard. There are many considerations and you can have performance problems when running with large datasets. Hence, SimpleDB is usually useful only for small projects.
SimpleDB is the only serverless database offered by AWS. If you want a better serverless solution, you would need to try other cloud providers. You currently have the following options: Google Firebase storage, Google Cloud Datastore, or FaunaDB.
SimpleDB is one of the oldest AWS services, announced in late 2007. However, it continues to be one of very few services that don't have a Management Console. If you want a GUI to easily query and manage your SimpleDB data, you can install a third-party solution. In this case, I suggest the SdbNavigator Chrome Extension as a good option. You only need to add an access key and a secret key to connect to your database. As a security measure, create a new user account using IAM with restricted privileges to SimpleDB.