What Are Preconditions? Setting the Stage for Use Cases

A decision table is a simple but powerful tool for organizing complex business rules and logic. Think of it as a spreadsheet for system design, where you can visually map out every possible scenario to see exactly what happens and why. It’s a tabular representation that shows conditions, actions, and the rules that connect them.

A Simple Analogy: The Traffic Light

Consider a simple traffic light. It has a set of rules:

• Rule 1: IF the light is red, THEN stop.
• Rule 2: IF the light is yellow, THEN slow down.
• Rule 3: IF the light is green, THEN go.

A decision table takes this simple “if/then” logic and expands it to handle dozens of conditions and actions at once, making it perfect for complex systems.

A Step-by-Step Example: ATM Cash Withdrawal

Let’s see how a decision table simplifies the logic of a common use case: withdrawing cash from an ATM.

As you can see, the table clearly shows how different combinations of conditions lead to specific actions. This makes it easy to spot missing scenarios and ensure your system handles every possibility.

Why Decision Tables Are So Useful

• Identify Gaps: By organizing your logic, you can easily find scenarios you may have forgotten to consider.
• Improve Communication: They provide a simple, shared visual aid for discussing complex rules with a team.
• Support Testing: Each row in a decision table is a ready-made test case, ensuring thorough and complete testing.

Automating the Process with Our Analyzer

Manually creating decision tables for a complex use case can be a lot of work. That’s why our Use Case Scenario Analyzer automates the entire process.

Simply provide your use case description (by typing, pasting, or generating it with our other AI app) and the analyzer will automatically:

• Identify and list all relevant Conditions.
• Identify and list all potential Actions.
• Generate a complete Decision Matrix that includes every scenario, such as “insufficient balance” or “insufficient ATM cash,” and maps it to the correct outcomes with easy-to-read checkmarks.