Question

I don’t think that I am understanding how CouchDB works. My impression is that everything runs on the client side, so wouldn’t that mean it is useless for storing user data because anyone can write a simple script to access that information? This doesn’t make sense to me, do I have it all wrong?

Answer 1

Aside from map-reduce and update operations, everything in CouchDB does run on the client. In this context, client means client connecting to the database server, which will usually be an application or script running on your web server. That’s the case for other database systems, too: to connect to a MySQL database from a PHP script, you need to use a MySQL client library.

One special thing about CouchDB is that instead of using its own transfer protocol (like other systems like MySQL do), it uses HTTP, which is implemented by almost every single available language out there. This makes the development of a CouchDB client extremely easy.

The other special thing about CouchDB is that its security model does allow you to let end users connect directly to the database. In such a situation, you would write a JavaScript application that runs entirely in the users’ browsers and queries the database through AJAX. The server would then authenticate the user and grant access only to those databases that the user is allowed to access, in either read-only or read-write mode. While this requires a bid of server-side scaffolding (to register new users and create a brand new database for them).

But you don’t have to. My company uses CouchDB as a general-purpose persistent storage that is completely invisible from the internet, and only our web server is allowed to access it.