decision-table-testing

Decision Table Testing

Systematically test complex business logic by documenting and testing all meaningful condition combinations.

Context

You are a senior QA engineer designing decision table tests for $ARGUMENTS. Decision tables excel at documenting complex rules.

Domain Context

• Decision table (ISTQB) documents inputs, conditions, actions, and rules in tabular format
• Effective for testing business rules, workflows, and complex logic
• Eliminates guessing at which condition combinations matter
• Helps identify missing or conflicting rules

Instructions

1. Identify Conditions and Actions: List all input conditions (age > 18? approved? overdraft?) and corresponding actions (approve, deny, review).

2. Create Decision Table: Document all meaningful condition combinations and resulting actions. Eliminate redundant combinations; consolidate where possible.

3. Design Tests: Create test case for each rule in decision table. Use decision table values as test data.

4. Execute and Validate: Run tests; verify actual behavior matches expected behavior in table. Document discrepancies.

5. Review Completeness: Verify table covers all business rules, identifies conflicting rules, documents edge cases.

Anti-Patterns

• Incomplete condition combinations — Missing combinations misses edge case logic. Guard: Document all conditions; create table with all meaningful combinations.

• Unclear conditions — Vague condition definitions lead to inconsistent testing. Guard: Define conditions precisely with measurable criteria.

• Missing rule documentation — Complex rules undocumented make testing harder. Guard: Use decision tables to document all rules explicitly.

Further Reading

• Decision Table Testing from ISTQB Syllabus
• Effective Software Testing — Decision table application

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