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Productivity Through Experience

What is a Business Rule?


A business rule is a declarative, plain English, statement of fact that defines a boundary between what does and does not constitute acceptable business conduct. It is controlled by your business policy makers. Examples include...

  • A trade must be interacted with a counterparty
  • The total amount of all journals in an accounting treatment must sum zero
  • A sales order cannot be submitted for approval unless it is associated with an agent
  • A salesmen must be awarded platinum grade if the total value of his sales occurring within the last complete financial period exceeds the platinum sales threshold

In the examples above the colour codes denote the components of each rule
  • Business Terms: nouns of the business, the core, unchanging concepts, managed in a business vocabulary
  • Fact Types: the relationships between these terms
  • Properties: the attribute values (e.g. dates, strings, etc) associated with specific terms
  • Assortments: specific instances of nouns that have a fixed value
  • Connectives: the words that bind rules together and which have predefined meaning

What is the Value of Business Rules to My Business?


All of these business rules are...
  • Business (not IT) Oriented: expressed succinctly using documented business terms (defined in a separate fact model);
  • Declarative: makes a statement about the business, but does not proscribe a sequence of operational behaviour or define a process;
  • Atomic: not subject to division or equivocation, defining a clear boundary between acceptable or non-acceptable behaviour;
  • Independent: capable of being completely understood in isolation of business process, or other rules

Because of these properties, rules are easier for business experts to review, understand, test and change than code. This results in greater safe agility (the ability to change your rules with a quick turn around time and no unintended consequences). Safe agility is the key value proposition of rules.

Read this article to better understand the business benefit of rules.

A important refinement to business rules is when they are combined into coherent sets, called business decisions.

Find Out More About Business Rules