Chapter 9 Using Business Rules

Defining business rules in an OOM

You can define a business rule which can be attached to the following objects in an OOM:

Domains

Classes

Interfaces

Attributes

Identifiers

Operations

Associations

Generalizations

Realizations

Dependencies

Types of business rule

In PowerDesigner, you can define several different types of business rules.

Rule type

Definition

Fact

Formula

Validation

Describes

Characteristics or properties of an object in the information system

Certainty or existence in the information system

Calculation employed in the information system

Constraint on a value in the information system

Example

A customer is a person identified by a name and an address

A client may place one or more orders

The total order is the sum of all the order line costs

The sum of the order totals for a given client must not be greater than that client’s allowance

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Sybase 7.5 manual Defining business rules in an OOM, Types of business rule, 253, Rule type, Describes