At the PASS Summit that is happening in Seattle at the moment Microsoft announced the “BI Semantic Model” (BISM).
It looks like BISM is something like the UDM that we now know from SSAS. While the UDM was the bridge between relational data to multidimensional data, BISM is the bridge between relational data to the column-based Vertipaq engine. Some compare BISM to Business Objects universes.
The next version of SSAS will be able to either run in the old “UDM” mode or in “BISM” mode, a combination is not possible. Of course this will have some radical consequences, because there are a few major differences between the two modes:
- The switch from multidimensional cubes to the in-memory Vertipaq engine
- The switch from MDX to DAX
So multidimensional cubes and MDX will be deprecated? No, not really, SSAS as we know it now will be a product in the future and will remain supported. But it looks like Microsoft will concentrate on BISM, mainly because multidimensional cubes and MDX are very difficult to learn. Microsoft wants to make BI more approachable and less difficult, just like with Self Service BI.
I would say that it’s really time to start learning PowerPivot and DAX right now, if you have not already started learning it. If Microsoft will focus on the new BISM/Vertipaq technology that will be the future if you ask me.
Chris Webb wrote an interesting article about BISM and it looks like he is not very enthusiastic about the strategy Microsoft takes here because this could be the end of SSAS cubes within a few years: “while it’s not true to say that Analysis Services cubes as we know them today and MDX are dead, they have a terminal illness. I’d give them two, maybe three more releases before they’re properly dead, based on the roadmap that was announced yesterday.”
What’s also very interesting is the comprehensive comment on this article from Amir Netz. He explains BISM and UDM will live together in Analysis Services in the future and MOLAP is here to stay: “Make no mistake about it – MOLAP is still the bread and butter basis of SSAS, now and for a very long time. MDX is mature, functional and will stay with us forever.”