CTFL_Syll2018 Exam Dumps : ISTQB Certified Tester Foundation Level (Syllabus 2018)

A decision table is a specification-based test technique that involves creating a table that shows the combinations of inputs and outputs for a system under test based on certain conditions and rules. A decision table can be used to design test cases that cover all possible scenarios and outcomes for a system under test. Some statements about decision tables are:

• I. Generally, decision tables are generated for low risk test items: This statement is false because decision tables can be generated for any level of risk test items depending on the complexity and variability of the system under test. Decision tables are especially useful for testing systems that have many inputs, outputs, conditions, and rules that affect their behavior or performance.
• II. Test cases derived from decision tables can be used for component tests: This statement is true because decision tables can be used to design test cases for any level or type of testing, including component tests. Component tests are tests that verify individual components or units of software in isolation from other components or systems.
• III. Several test cases can be selected for each column of the decision table: This statement is true because each column of the decision table represents a unique combination of inputs and outputs for the system under test based on certain conditions and rules. Therefore, each column can be used as a basis for selecting one or more test cases that cover that combination.
• IV. The conditions in the decision table represent negative tests generally: This statement is false because the conditions in the decision table can represent both positive and negative tests depending on the requirements and expectations of the system under test. Positive tests are tests that verify that the system under test behaves as expected under valid or normal inputs or conditions. Negative tests are tests that verify that the system under test handles errors or exceptions gracefully under invalid or abnormal inputs or conditions.

You can find more information about decision tables in [A Study Guide to the ISTQB® Foundation Level 2018 Syllabus], Chapter 4, Section 4.2.

One of the basic principles of testing is that for a software system, it is not possible under normal conditions to test all input and output combinations because they are too many and too complex to cover within a reasonable time and budget. Therefore, testers have to select a subset of inputs and outputs that are representative and relevant for testing based on criteria such as requirements, risks, priorities, etc. This principle implies that testing cannot prove that a software system is defect-free or has a certain level of quality because there might be some untested inputs or outputs that could reveal defects or failures. Testing can only provide information about the quality and risk level of a software system based on the observed behavior and results under certain conditions and assumptions. You can find more information about the basic principles of testing in A Study Guide to the ISTQB® Foundation Level 2018 Syllabus, Chapter 11.

Percentage of work done in test environment preparation is a metric that measures how much of the required test environment setup has been completed. This metric is useful for monitoring the test progress because it indicates whether the test environment is ready for executing the planned test cases or not.