A C++ library implementing column-oriented bitmap indexes.

In its current format, this library indexes flat files to a bitmap-based column store. It can scale up to one hundred million attribute values, and to billions of lines. Support for projection indexes is also available.

For compression, it uses with a form of word-aligned compressin akin to the Word-Aligned Hybrid encoding (WAH) called Enhanced Word-Aligned Hybrid encoding (EWAH) which is particularly suitable to 64-bit processors.

It should build without a problem on MacOS and Linux.

See doc/index.html for the documentation.

Reference:

Daniel Lemire, Owen Kaser, Kamel Aouiche, Sorting improves word-aligned bitmap indexes. Data & Knowledge Engineering (to appear). http://arxiv.org/abs/0901.3751

Slides: http://www.slideshare.net/lemire/all-about-bitmap-indexes-and-sorting-them