- #ORF09 An introduction to the RETE algorithm
- #ORF09 Playing With the Rules Presentation
- #ORF09 Rule Patterns and Features Presentation
- #ORF09 Early Alert System Presentation
- #ORF09 Engineer’s perspective on Rule Technology Keynote
- #ORF09 Enterprise Architecture Presentation
- #ORF09 Enterprise Architecture Presentation Part II
- #ORF09 Model Driven Approach for BRMS Presentation
- #ORF09 Production Rule Systems
- #ORF09 Graph Based Knowledge Bases and Rules Presentation
- #ORF09 Truth versus Useful Lies Presentation
- #ORF09 Automated Verification of rules Presentation
- #ORF09 Agile Business Rule Development Presentation
- #ORF09 Rule Classification First Presentation
- #ORF09 Rule Violation and Over-Constrained Problems Presentation
- #ORF09 Generating Rules from UML presentation
- #ORF09 What’s Different about Rules in CEP Presentation
- #ORF09 Measuring your Rules’ KPI Presentation
- #ORF09 Designing a System of Rule Based Agents Presentation
- #ORF09 Extending General Purpose Engines Presentation
- #ORF09 Programming Rules using a spreadsheet interface
- #ORF09 Practical and Modern RBE Presentation
- #ORF09 Temporal Reasoning Presentation
- #ORF09 Business Rules in the Cloud Presentation
- #ORF09 October Rules Fest Think Tank
- #ORF09 October Rules Fest Think Tank – Part II
- #ORF09 CLIPS implementation of RETE Presentation
- #ORF09 Complex Event Processing Models Presentation
- #ORF09 Distributed Programming with Agents Presentation
- #ORF09 making Parallelism Available to Rule Developers Presentation
David Holz started his presentation saying that the goal of his company is to eliminate all programming except in rules! Obviously it is a little tongue in cheek. But basically, how do you take rules beyond business rules?
They are trying to do as much as they can in rules and can see that writing rules using that approach has some advantages. Some of the disadvantages, is a loss of low level control and some performance in execution, but claims gains in productivity.
Some of the targets for declarative style are:
- Configuration
- Partial failure recovery
- Permissions Systems
- Job Control, workflows, state machines
- Continuous integration
- GUI layout and control
Based on that list, I’m not sure we are quite ready for this type of programming, but in theory it could be applied.
To achieve this, they created a Unified Rule Engine Model. This requires that all data is actually stored in Facts and you have a single knowledge base for the entire application suite. Then the rule engine controls everything else.
The challenges in having a Unified Rule Engine Model is that all the Facts need to be persistent, so your knowledge base is no longer simply in memory, it requires things to be permanent. Another challenge is how to support updates of rules without re-firing of a rule that was changed. Scalability is obviously another huge challenge.
My first impressions on all of this is that it is very interesting from an academic perspective, but I am not sure how much can be applied in the short term. Maybe it will have potential in the long term future, but I have doubts on the short term and medium term potential of this type of architecture.
The hurdles to making this production ready, stable enough, with the persistence challenges are very hard to get over. Then you need to have successful implementations, and to start convincing people that this is the way to go in the future from an architecture point of view. Hmmm.
The presentation then talked about Design Patterns in the Object Oriented World, and how it help software development. He wants to bring this to the rules world.
Some of the rules patterns he presented:
- A consumption pattern (and some other related patterns
- Event queue pattern
- Continuation Pattern
Still a very interesting presentation although I’m not sure how the first part could really be applied today. The Design Pattern part of the presentation has a lot more potential and I would be interested in seeing more on the topic in the future which David Holz is hoping to work on in the near future.
Tags: Business Rules, Conferences, ORF09





Our rule engine server has been actually deployed internally for a few months now, with persistent facts and rules, managing our state and doing delegation to libraries written in other languages.
I’m pretty sure I mentioned that in the talk, though it might have been missed.
We were careful to present only that which we had already running, or had finished technical design on, so that we wouldn’t be broadsided by any unexpected questions.