Tag Archive For "Dimensional Modeling"
A Closer Look at the Coverage Fact Table
One of the more interesting types of fact tables is the factless fact table for conditions – also known as Coverage Fact table by Kimball purists. I was recently reminded of this type of fact table while reading Star Schema: A Complete Reference in which Chris Adamson (b | t) describes the factless fact table for …
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. …
Conformed Dimensions: the Key to Cross Process Analysis
Over the past few months, I’ve been spending a lot of time reading about, thinking about, and working on conformed dimensions for a client. The reason is simple, conformed dimensions enable businesses to track richer (and typically more complicated) metrics spanning multiple business processes. Note: there are many additional benefits of conformed dimensions…for a more …
Dimensional Modeling: Junk vs Degenerate
Two commonly misunderstood dimensional modeling techniques are Junk Dimensions and Degenerate Dimensions. This post is aimed at clearing up the confusion and providing some context and use-cases for each. Junk Dimensions There are certain scenarios where you will find that the source for a fact table contains a bunch of low-cardinality attributes that don’t really …