Lemur OLAP Library

This project is hosted on Savannah

Update (June 2012): This library is no longer supported. Please don't use it for anything that matters.


As a crude approximation, we could say that Lemur OLAP is an open source (GPL) Hybrid OLAP library written in C++ but callable from other languages like Java or Python.

To our knowledge, there is no free software low level OLAP library implementing Hybrid OLAP. There is Mondrian which is a great Java-based ROLAP engine, but we believe that a smart C++ implementation can outperform a DBMS (using Mondrian) platform for many tasks including text mining, science intelligence and so on.

To be fair though, the primary goal of this library was to support our research interests since our goal are probably too ambitious to deliver timely usable code.

We offer basic operations like slicing, rollups, dicing. Attribute values must be stored separately however: we only provide the core engine.


If you are just looking for an OLAP interface to your favorite database, please check Mondrian. It is written in Java and uses ROLAP. It is quite good and a lot more user-friendly than Lemur (but it doesn't do MOLAP, HOLAP, nor is it in C++). It supports MDX and XMLA 1.0 which Lemur OLAP will never support.

Palo is a MOLAP server than can run under Linux, interface with Excel, PHP and Java (at least these 3). It might be an excellent solution if your cubes have a small volume.


GPL, of course.

Who are we?

The project was lead by Daniel Lemire, professor at the University of Quebec at Montreal (UQAM), and Owen Kaser, associate professor at the University of New Brunswick (Saint John).

The following students have been involved:

We thank Steven Lembark from Cheetahmail for some valuable contributions including a cleaner file tree.

Where's the source?

You can browse Steven Lembark's CVS tree; there are instructions on how to grab a copy of the CVS tree. As of May 1st 2006, there are some small differences in the source code between the internal version (see tar ball below) and Steven's tree due to incomplete merges.

lemurolap_01052006.tar.gzMay 1st 2006 (most recent)102 Kb
lemurolap_16032006.tar.gzMarch 16th 2006100 Kb
lemurolap_07012006.tar.gzJanuary 7th 200684 Kb
lemurolap_16082005.tar.gzAugust 16th 200553 Kb
lemurolap_12082005.tar.gzAugust 12th 200552 Kb
lemurolap_25072005.tar.gzJune 25th 200551 kB
lemur_code.zipFebruary 19th 2004 (oldest)1 034 kB

If you are lucky, it runs under GNU/Linux.


This library is no longer supported. It is probably useless.

Who do you complain to?

This library is no longer supported. If it fails to be useful, please just move on.