Decision Tables

A Decision table represents conditions and the respective actions to be taken to address them, in a structured tabular format.

It is a powerful tool to debug and prevent errors. It helps group similar information into a single table and then by combining tables it delivers easy and convenient decision-making.

Creating Decision Table

To create the decision table, the developer must follow basic four steps:

      Identify all possible conditions to be addressed

      Determine actions for all identified conditions

      Create Maximum possible rules

      Define action for each rule

Decision Tables should be verified by end-users and can lately be simplified by eliminating duplicate rules and actions.

Example

Let us take a simple example of day-to-day problem with our Internet connectivity. We begin by identifying all problems that can arise while starting the internet and their respective possible solutions.

We list all possible problems under column conditions and the prospective actions under column Actions.

 

Conditions/Actions

Rules

Conditions

Shows Connected

N

N

N

N

Y

Y

Y

Y

Ping is Working

N

N

Y

Y

N

N

Y

Y

Opens Website

Y

N

Y

N

Y

N

Y

N

Actions

Check network cable

X

 

 

 

 

 

 

 

Check internet router

X

 

 

 

X

X

X

 

Restart Web Browser

 

 

 

 

 

 

X

 

Contact Service provider

 

X

X

X

X

X

X

 

Do no action

 

 

 

 

 

 

 

 

Table : Decision Table – In-house Internet Troubleshooting