Decision table testing is used to analyze combinations of inputs to determine the appropriate outputs, often based on specific rules or conditions.
For the problem statement:
* Rule 1: (Withdrawal = Allowed, Balance = Sufficient, Fast Cash = True, Correct PIN = True)
* Outcome: Transaction = Approved
* Rule 4: (Withdrawal = Allowed, Balance = Sufficient, Fast Cash = True, Correct PIN = False)
* Outcome: Transaction = Declined
The additional test cases are:
* DT1: (Withdrawal = Allowed, Balance = Insufficient, Fast Cash = True, Correct PIN = True)
* Outcome: Transaction = Declined
* DT2: (Withdrawal = Allowed, Balance = Sufficient, Fast Cash = False, Correct PIN = True)
* Outcome: Transaction = Approved
* DT3: (Withdrawal = Allowed, Balance = Insufficient, Fast Cash = True, Correct PIN = False)
* Outcome: Transaction = Declined
* DT4: (Withdrawal = Allowed, Balance = Sufficient, Fast Cash = False, Correct PIN = False)
* Outcome: Transaction = Declined
From the given test cases, DT2 covers the scenario where Fast Cash is False, which is not covered in the initial cases. DT3 covers the case where Balance is Insufficient and PIN is incorrect.
Combining Rules 1 and 4 with DT2 and DT3 covers all the scenarios.
References:
* Certified Tester Foundation Level v4.0
* 10 Sample Exams ISTQB Foundation Level (CTFL) v4.0