Compare

NextDB.net is the only relational database whose primary programming API is available as a JavaScript library. It is the only relational database that requires no serverside programming. Only NextDB allows you to extract all your data in an open format (no lock-in). Compare to these alternatives:

Amazon Web Services

Amazon's SimpleDB cannot be accessed directly from JavaScript. This is because Amazon Web Services (AWS) requires every request to be signed by the developer's secret key. AWS's SimpleDB lacks the basic relational capabilities. SimpleDB locks your data in. You cannot extract your data en masse in an open format.

Google App Engine

Google's App Engine requires you to write serverside Python or Java. Not a serverside programmer? You're out of luck. App Engine runs on the server, so you have to develop and debug server code. Like Amazon's SimpleDB, App Engine is not a relational database. App Engine locks your data in. You cannot extract your data en masse in an open format.

Web Hosting With MySQL

There are numerous web hosting companies that allow you to write PHP (Java, Perl, etc) and connect to a MySQL instance. However, once again these obviously require serverside programming, and tuning of the database.