Entries Published On February, 2014
Types of Fact Tables
In a presentation I’ve been delivering lately, Bus Matrix – the Foundation of your Dimensional Data Model, I briefly cover the hierarchy of an enterprise and how it can be conceptually broken down and mapped into a dimensional model. A single enterprise typically contains many business areas (e.g. Sales, Manufacturing, Finance) A single business area (e.g. …
The Best Book On Dimensional Modeling
The Data Warehouse Toolkit by Ralph Kimball has been read cover to cover by most Data Warehousing and Business Intelligence industry professionals. It is perhaps the most popular text on dimensional modeling known to mankind. However, it is not the best book on dimensional modeling. These may seem like pretty bold claims, yet I feel confident …
MDX: ParallelPeriod Is Not Calendar Aware (Part 2)
In the last post, we explored the ParallelPeriod function in a bit of detail and then used a contrived example to highlight a particular edge case that needs to be explicitly handled when the number of children differs between the 2 periods. Specifically, we looked at a prior month calculation and showed that calculating the …
MDX: ParallelPeriod Is Not Calendar Aware
ParallelPeriod is one of the more commonly used MDX functions out there. It’s primary use is in “prior period” calculations such as Prior Year sales (which in turn can be used to calculate Year-over-Year Change in sales) as well as Rolling Averages: Create Member CurrentCube.[Measures].[Internet Sales Amount – Prior Year] As ( ParallelPeriod( [Date].[Calendar].[Calendar Year] …