Countly uses MongoDB engine to persistently store and retrieve analytics data. MongoDB is a leading NoSQL with JSON style documents, which fits great with both capabilities of Countly and serverside environment NodeJS.
You can read more about MongoDB on their official website: http://www.mongodb.org/
For SQL database users, there are some changes in terminology that you should become familiar with.
|SQL term||MongoDB term|
Additionally you should know that documents may have properties many levels deep, unlike SQL rows. So for some of you Countly database scheme may seem like a nightmare, but it was designed with performance in mind, for both storing and retrieving data, thus sometimes it can be far from easily understandable.
For enterprise edition, countly divides data in 2 databases:
- countly - common statistics for users and metrics
- countly_drill - deeper insight on data relations
There are also other third party libraries available, as Mongo-Express: https://www.npmjs.org/package/mongo-express
There are also other solutions, that will help you to easily set up REST API to query Mongo databases. You may find solution suitable for your needs and environment here: http://docs.mongodb.org/ecosystem/tools/http-interfaces/