Pilosa is an open source, distributed bitmap index.

It is designed primarly for speed and horizontal scalability. If you have data with billions of objects that can have millions of possible attributes, and you want to explore those relationships, Pilosa can help you.

“What attributes are the most common?”, “Which objects have these specific attributes?”, “What groups of attributes often appear together?” Pilosa is designed to answer these types of queries in real time, suitable for use with high rate data streams, or to power a user interface.

Once you have Pilosa installed, the getting started guide will show you the basics of interacting with Pilosa and give you some pointers for deeper exploration.