Pilosa: An open source, distributed index

Technically, it is very interesting -- it uses Roaring Bitmaps under the hood and builds a query engine on it. So an easy way to think about it is that it maps categorical data into a giant compressible distributed bitmap.<p>I&#x27;ve been planning to see if I can (mis)use it as an OLAP replacement but I haven&#x27;t had time to get to it.

Source code:<p><a href="https:&#x2F;&#x2F;github.com&#x2F;pilosa&#x2F;pilosa" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;pilosa&#x2F;pilosa</a>

&gt;Pilosa is a standalone index for big data. Its goal is to help big data storage solutions support real time, complex queries without resorting to pre-computation or approximation. Pilosa achieves this goal by implementing a distributed bitmap index which provides a compact representation not of the data itself, but of the relationships present in the data.<p><a href="https:&#x2F;&#x2F;www.pilosa.com&#x2F;pdf&#x2F;PILOSA%20-%20Technical%20White%20Paper.pdf" rel="nofollow">https:&#x2F;&#x2F;www.pilosa.com&#x2F;pdf&#x2F;PILOSA%20-%20Technical%20White%20...</a>

Not sure who this document is aimed to. It&#x27;s not technical enough to appeal to programmers that are working closely with Pilosa. And it&#x27;s not written in a way to make it easy to understand for people that don&#x27;t know anything about Pilosa (such as myself). I mean a subtitle called &quot;Time Quantum&quot; is enough to make me confused. Would appreciate a more generic &quot;what is this&quot; intro if possible.

How do you handle race conditions? E.g. an app updated the persistent store but crashed before it could update Pilosa?

&quot;Continuous Analysis on Really Big Data - Pilosa is an open source, distributed bitmap index&quot; <a href="https:&#x2F;&#x2F;www.pilosa.com&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.pilosa.com&#x2F;</a>

Any chance there&#x27;ll be some built-in support to perform collaborative filtering? Seems like a database of relations like this would be awesome for user-based collaborative filtering.