Advanced⏱ 7 min read

Decision Table Testing

Decision table testing models complex business logic with multiple conditions and their resulting actions in a tabular format. It is exceptionally powerful for testing rules-heavy systems where different combinations of inputs produce different outputs.

◈Key Points

A decision table has: Conditions (inputs), Actions (outputs), and Rules (unique combinations of conditions).
Each column in the table is a test case — the table itself becomes the test suite.
For N binary conditions, there are 2^N possible rules — decision tables force you to consider all of them.
Collapse equivalent rules (same actions for multiple condition combinations) to reduce test count.
Ideal for: insurance pricing engines, discount calculation logic, approval workflows, access control rules.

⚡ Expert Pro Tip

If a developer can't give you a decision table for complex business logic, build one yourself and walk them through it. You'll often find missing or contradictory requirements in the process.