✍️ Test Case Design
Equivalence Partitioning, Boundary Value Analysis, Decision Tables, and State Transition.
Why Use Test Design Techniques?
Test design techniques maximize defect detection efficiency while minimizing the total number of test cases needed.
Equivalence Partitioning (EP)
Divides input data into valid and invalid partitions. Test cases select representative values from each partition.
| Input Field | Valid Partition | Invalid Partition Low | Invalid Partition High |
|---|---|---|---|
| Age (18 - 60) | 18 to 60 (e.g. 25) | < 18 (e.g. 15) | > 60 (e.g. 75) |
| Password Length (6 - 12) | 6 to 12 chars (e.g. 'pass123') | < 6 chars (e.g. 'abc') | > 12 chars (e.g. 'pass1234567890') |
Boundary Value Analysis (BVA)
Tests the boundaries between input partitions (Min-1, Min, Min+1, Max-1, Max, Max+1). Defect concentration is highest at boundaries.
| Field Constraint | Boundary Tested | Test Value | Expected Result |
|---|---|---|---|
| Age range 18 to 60 | Min - 1 | 17 | Reject / Error |
| Age range 18 to 60 | Min (Boundary) | 18 | Accept / Success |
| Age range 18 to 60 | Max (Boundary) | 60 | Accept / Success |
| Age range 18 to 60 | Max + 1 | 61 | Reject / Error |
Decision Table Testing
Ideal for complex business logic involving multiple combinations of conditions.
| Conditions / Actions | Rule 1 | Rule 2 | Rule 3 | Rule 4 |
|---|---|---|---|---|
| Valid Username? | Yes | Yes | No | No |
| Valid Password? | Yes | No | Yes | No |
| Action: Grant Access | SUCCESS | FAIL | FAIL | FAIL |