Tips & Tricks. Be aware of Month->Week hierarchy in DeepSee
You know, that when we build hierarchies in DeepSee dimension all the members of lower level should be the part of one member of the higher level.
If not you'll get some empty results in MDX queries with this hierarchy.
With Time dimensions the obvious valid hierarchy is Year->Month->Day, cause every Month consists of one Year and every day consists of one month.
But be aware of using Year->Month->Week->Day hierarchy. In this case, there are some weeks in the year (most of them), which consist of two months. As a result, you can get unpredicatable empty results in your MDX queries with such a dimension.