Chris Webb's BI Blog: Open Source BI

olap4j

Tue, 03 Jul 2007 12:30:29 GMT

I've just come across olap4j (http://www.olap4j.org/) which might be of interest for anyone out there working with Java to access OLAP cubes - as the website says, it's like JDBC for OLAP (and so I guess you can also say it's like ADOMD.Net for Java). It's designed to work with a range of OLAP servers including AS2005. The interesting thing about it for me isn't the cross-platform support, though, but that it in addition to support for MDX it will have an API for programmatically generating queries - something that I think would be useful to have in Microsoft's own data access layer. Implemented correctly it would take away the need for programmers to have to learn about how to write efficient MDX and hopefully bring about a kind of standardisation of queries which would make writing calculations on the cube easier.

Cubulus - an open source OLAP engine

Sat, 21 Apr 2007 21:45:12 GMT

I've had an email from Alexandru Toth about an open source OLAP project he's working on. Here's what he had to say:

I am developing an Open Source OLAP project called "Cubulus". There is a presentation material at http://cubulus.sourceforge.net/ , and an online demo at http://alxtoth.webfactional.com/ .The source code is at http://sourceforge.net/projects/cubulus/ .

In brief, Cubulus is an analytic engine + slice&dice web interface on top of relational database (MySQL at the moment) . It caches calculated cells, and is able to parse basic MDX queries. Project is in early alpha, and runs on Mac OS X, on Windows .. and on Linux too :-)

Perhaps not ready for the enterprise just yet, but still a worthy effort and any new OLAP that supports MDX is ok with me.

Playing away from home with Pentaho and Mondrian

Thu, 31 Aug 2006 13:21:06 GMT

Back in March, when I announced on this blog that I was going to set myself up as an independent consultant, I mentioned that I would be interested in doing some MDX work on other OLAP servers that support the language. Very soon afterwards I got an email from Nick Goodman at Pentaho asking me if I was interested in finding out a bit more about the open source OLAP server Mondrian and helping the open source BI community come to grips with MDX. How could I refuse?

Anyway, Nick pointed me in the direction of a very quick and easy to install demo of all of the Pentaho platform including Mondrian:

http://prdownloads.sourceforge.net/pentaho/pentaho_demo-1.2.RC1.341.zip?download

You literally download it (it's about 100Mb), unzip it, click on 'start-pentaho.bat' and go to http://localhost:8080/pentaho/ and you're there. Click on the 'Steel Wheels' sample and you can see demos of their reporting, olap and dashboarding tools. I've only really had a look at the olap stuff so far: in the Steel Wheels sample you click on 'Pentaho Analysis' and then 'Territory Analysis by Year' and you'll see a pivot table (JPivot) and a graph; click on the MDX button at the top and you'll see, and can alter, the MDX behind it. My first impression of this - and Pentaho Analysis is just rebranded Mondrian as far as I understand it - is just how conceptually similar it is to AS2K. Anyone coming from a Microsoft BI background will feel very at home with it. There's a ton of documentation on Mondrian here:

http://mondrian.sourceforge.net/

...if you'd like to find out more.

Of course now I feel all guilty and adulterous (well, ok, not that bad) having strayed away from Analysis Services, but don't worry - it will always remain my true love. But given that there's such a shortage of people even in the Microsoft BI world that understand MDX I think there must be massive untapped demand out there for people who have cross-platform MDX skills: even though platforms like Essbase and SAP BW support MDX I'm sure you could count the number of Essbase and SAP BW consultants out there with anything more than a superficial knowledge of MDX on the fingers of one hand.