This is the third of a multiple part on the topic of business rules categorization.
So far, we have seen a definition for business rule which is very broad and needed to be broken down a bit more. I then performed a search on the use of the terms “business rules” which showed me that a lot of people refer to those words. I then was hoping to find a classification of business rules that would include all of that and put some clarity into it.
As part of my search for a categorization, I obviously performed a search on existing classifications. This post will be about the main classifications I have found and my thoughts on each of them.
Note that my own classification will not appear in this post since this is just an overview of other classifications I have found. This might not be of general interest to everyone and readers can actually wait for (or go to) the next post in this series to see what I proposed.
Ronald G. Ross’ BRS Rule Classification Scheme
The obvious place to start is to look at Ronald G. Ross’ work on the subject. He summarizes it in an article available on brcommunity.com.
His classification contains the following three main categories (for more details see his article):
- Rejector (Constraint)
- Computation Rules
- Derivation Rules (Inference rules)
- Projector (Stimulus / Response Rules)
- Executive (Trigger)
This is a good classification but as I was looking at this classification I realized that I was looking for a classification that would allow me to identify in which type of system the rules would be implemented, not just what type of rule it was. I will explain that a bit further in the article, for now let us continue a quick review of other classifications.
Barbara von Halle’ classification from Business Rules Applied
In her book, she lists a few classifications from other sources and proposes her own classification which goes as follows:
- Mandatory Constraint
- Action Enabler
In this case, some of the classification is very similar to the BRS Rule classification. The main difference here is Guideline which is different. As for Term and Fact, as far as I am concerned they are not types of rules but then again this isn’t my classification now is it?
One thing I liked when I read through the classification is some of Versata’s classification which I will detail later in this post.
Inastrol’s Business Rule classification scheme
Terry Moriarty’s company Inastrol uses the following classification:
- Eligibility (Inference)
- Validation (Constraint)
- Computation (Calculation)
- Process (Even-Condition-Action / Action Enabler)
- Authority (Policies)
I found interesting that this was the first use of the word “Process” since some rules are obviously associated to processes.
Versata’s classification 
As mentioned above, Versata had some interesting categories listed in von Halle’s book. I then went and searched Versata’s web site and also found some archives and I compiled the following list which they used at one time or another:
- Referential Integrity
In this list which I compiled from different sources, I liked the distinction between process, data, transaction, presentation and decision rules since chances are these types will be implemented in a different product.
One thing that is interesting is that most if not all of the classifications can be mapped back to the BRS Rule classification.
Well there you have it. That was my inspiration for building my own classification. In my next post, I will detail this new classification.
 The BRS Rule Classification Scheme
 von Halle, Barabara, 2002, Business Rules Applied, Wiley