Each column in a decision table represents a condition or an action. The column header identifies an object being tested in a condition or the target of an action.
The columns of a decision table define the conditions and actions that apply to the rules contained in the table. As shown in the following table, condition columns 1 are unshaded, while action columns 2 are shaded.
Each row in the table corresponds to one rule. The actions of a given rule are performed when all of its conditions are valid. For example, the rule corresponding to the second row in the above figure reads as follows:
if
all of the following conditions are true:
- the loan grade is A
- the amount of the loan is between 100000 and 300000
then
set the Insurance required to true
set the Insurance rate to 0.001
Split columns
Conditions can be split across more than one column of the table when the rule statement they represent contains more than one value. For example, the following condition requires you to specify a value for both <min> and <max>.
if the age of the customer is between <min> and <max>
In a decision table, this condition is represented in the Age column, but across two subcolumns: one for the value <min> and one for the value <max>:
| Age | ||
| Min | Max | |
| 1 | 18 | 25 |
| 2 | 26 | 40 |