ISTQB Updated ISTQB-CTFL Exam Questions and Answers by miran

Boundary value analysis is not an experience-based technique, but rather a specification-based technique (also known as black-box technique). Experience-based techniques are techniques that rely on the tester’s knowledge and intuition to derive and select test cases based on their experience with similar systems, technologies, domains, risks, etc. Some examples of experience-based techniques are error guessing, exploratory testing, fault attack, checklist-based testing, etc. Specification-based techniques are techniques that rely on the tester’s analysis and interpretation of the requirements or specifications of the system under test to derive and select test cases based on some criteria or rules. Some examples of specification-based techniques are equivalence partitioning, boundary value analysis, decision table testing, state transition testing, etc. Verified References: A Study Guide to the ISTQB® Foundation Level 2018 Syllabus - Springer, page 31.

The minimum number of test cases needed to cover the full decision table associated with this scenario is 6. This is because the decision table has 4 conditions (type of customer and amount of sale) and 4 actions (bonus percentage). The conditions have 2 possible values each (Basic or Premium, and G1, G2 or G3), so the total number of combinations is 2 x 2 x 2 x 2 = 16. However, not all combinations are valid, as some of them are contradictory or impossible. For example, a sale cannot be both less than 300 euros and greater than 2000 euros at the same time. Therefore, we need to eliminate the invalid combinations and keep only the valid ones. The valid combinations are:

Type of customer

Amount of sale

Bonus percentage

Basic

G1

3%

Basic

G2

5%

Basic

G3

7%

Premium

G1

5%

Premium

G2

7%

Premium

G3

10%

These 6 combinations cover all the possible values of the conditions and actions, and they are the minimum number of test cases needed to cover the full decision table.

The purpose of a review is to find defects and improve the quality of the work product, not to criticize or blame the author. Reporting defects objectively means describing them factually and constructively, without using negative or emotional language that could offend the author or damage their motivation. This way, the author can take the feedback positively as an effort at improving the product and not as a personal assault. Verified References: A Study Guide to the ISTQB® Foundation Level 2018 Syllabus - Springer, page 138.

 If a program got 100% decision coverage in a test, then it is guaranteed that every executable statement is covered. Decision coverage (also known as branch coverage) is a type of structural coverage (also known as white-box coverage) that measures how many decision outcomes have been exercised by a test suite. A decision outcome is a possible result of a decision point (such as an if-then-else statement) in a program’s code. Decision coverage requires that each decision point has both true and false outcomes executed at least once by a test suite. Decision coverage implies statement coverage, which is another type of structural coverage that measures how many executable statements have been executed by a test suite. Statement coverage requires that each executable statement is executed at least once by a test suite. Therefore, if a program got 100% decision coverage in a test, then it also got 100% statement coverage in a test, which means that every executable statement is covered. The other options are not guaranteed to be true if a program got 100% decision coverage in a test. Every output equivalence class has been tested and every input equivalence class has been tested are not guaranteed to be true if a program got 100% decision coverage in a test, because equivalence classes are based on functional requirements or specifications, not on code structure or logic. Equivalence classes are used in specification-based testing (also known as black-box testing), which is a type of testing that does not consider the internal structure or implementation of the system under test. Decision coverage is used in structure-based testing (also known as white-box testing), which is a type of testing that considers the internal structure or implementation of the system under test. Therefore, achieving 100% decision coverage does not imply achieving 100% equivalence class coverage. The “dead” code has not been covered is not guaranteed to be true if a program got 100% decision coverage in a test, because dead code (also known as unreachable code) is code that can never be executed due to logical errors or design flaws. Dead code can reduce readability and maintainability of the code, as well as increase complexity and size. Decision coverage does not account for dead code, as it only considers the decision outcomes that are possible to execute. Therefore, achieving 100% decision coverage does not imply that the dead code has not been covered. Verified References: A Study Guide to the ISTQB® Foundation Level 2018 Syllabus - Springer, page 36.