Decision Tables

A Decision Table is a tabular representation of inputs versus rules/cases/test conditions. It is a very effective tool used for both complex software testing and requirements management. Decision table helps to check all possible combinations of conditions for testing and testers can also identify missed conditions easily. The conditions are indicated as True(T) and False(F) values.

Purpose:

The purpose of a decision table is to show a logical structure, with all possible combinations of conditions and resulting actions.They provide a clear method to verify testing of all pertinent combinations to ensure that all possible conditions, relationships, and constraints are handled by the software under test.

How to create a decision table?

At first fill in the Y/N patterns. Next, each column or rule represents a different set of conditions, analyze the logic and show the outcome of each rule.

Example:

Importance:

It assists in development process with developer to do a better job. Testing with all combination might be impractical.
A decision table is basically an outstanding technique used in both testing and requirements management.
It is a structured exercise to prepare requirements when dealing with complex business rules.

Decision Table Designed for Test looks like: