iAnywhere Water System User Manual

Chapter 9 Using Business Rules
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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 Describes Example
Definition Characteristics or properties of
an object in the information
system
A customer is a person identified
by a name and an address
Fact Certainty or existence in the
information system
A client may place one or more
orders
Formula Calculation employed in the
information system
The total order is the sum of all
the order line costs
Validation Constraint on a value in the
information system
The sum of the order totals for a
given client must not be greater
than that client’s allowance