I’m still late with blog reading and sometimes I discover interesting things one or two months later than the original posting. I just read the SQLCAT analysis of the several solutions available to handle multiple parent-child hierarchies within a single dimension. The multiple hierarchies pattern described in my many-to-many paper has been used (with some variations) and now I have the “SQLCAT certification” that this model is faster than others!
I think there is space for improvement in this area and the many-to-many space is still a relatively unexplored space. If you have experience adopting those models, please share your knowledge – and if you are shy, write me directly and I’ll post the interesting data.