Seven Databases in Seven Weeks, 2nd Edition

Hu(mongo)us

Mongo hits a sweet spot between the powerful queryability of a relational database and the distributed nature of other databases, like HBase. Project founder Dwight Merriman has said that MongoDB is the database he wishes he’d had at DoubleClick, where as the CTO he had to house large-scale data while still being able to satisfy ad hoc queries.

Mongo is a JSON document database (though technically data is stored in a binary form of JSON known as BSON). A Mongo document can be likened to a relational table row without a schema, whose values can nest to an arbitrary depth. To get an idea of what a JSON document is, check this out:

In some ways, document databases have an opposite workflow compared to relational databases. Relational ...