Decision Table Testing: All you need to know about it

A software testing approach known as "Decision Table Testing" is used to examine how the system responds to various input combinations. The various input combinations and the accompanying system behavior are tabulated in this methodical technique. 

 

As the causes and consequences for thorough test coverage are recorded in this table, the decision table is also known as a Cause-Effect table. Black-box testing methods like decision table testing, which tests two or more inputs with a logical relationship, are frequently employed.

 

What is a Decision Table?

 

In several engineering disciplines, decision tables are utilized to describe complex logical relationships. The software and its requirements management can be tested extremely effectively with the help of this testing. Decision tables provide a tabular depiction of many combinations of input conditions, where the conditions are expressed as True(T) and False. The result may depend on many different input circumstances (F). Additionally, it offers a list of circumstances and the accompanying actions that must be taken during testing.

 

As the causes and consequences for thorough test coverage are recorded in this table, the decision table is also known as a Cause-Effect table. Black-box testing methods like decision table testing, which tests two or more inputs with a logical relationship, are frequently employed.

 

Also Read | Types of Software Testing

 

Decision Tables: Why Are They Important?

 

Although both boundary value testing and equivalent partition testing are effective at ensuring coverage, none of them will be helpful in situations when the system behaves differently depending on the inputs used.

 

A testing team can design tests more effectively by creating a decision table. Decision tables are beneficial for expressing complex business rules as well as for testers who want to understand how various input combinations affect the outcome. 

 

Testing these combinations will be difficult if there are many possible input combinations in the project at hand. This is true of many applications. Making a decision table is one of the better approaches to carrying out a test that has good coverage in situations like these.

 

Also Read | What is Regression Testing? Working & Types

 

Components of Decision table:

 

The decision table in software testing comprises 4 parts, which are separated into portions and are listed below:

 

1. Condition Stubs: The conditions that are utilized to decide on a certain action or combination of actions are listed in this initial top left section of the decision table.

 

2. Action Stubs: In the decision table's initial lower left section (below the condition stub), all feasible actions are listed.

 

3. Condition Entries: The values for the condition entry are entered in the decision table's upper right corner. The table's condition entries section has numerous rows and columns that are referred to as rules.

 

4. Action Entries: In the action entry, each entry has a related action or set of actions in the decision table's lower right corner. These values are referred to as outputs.

 

How Should Decision Tables Be Used When Creating Tests for Software?

 

Finding a suitable function or subsystem that reacts as suggested by events or a combination of inputs is the primary objective. The system shouldn't have too many input sources because then the number of combinations will become unmanageable.

 

It is wiser to manage a large number of conditions by breaking them up into smaller groups and handling each group separately. When you have determined which viewpoints should be joined, you put them into a table and list all of the possible combinations of true and false for each angle.

 

Types of Decision table:

 

The decision tables can be divided into two categories, which are listed below:

 

1. Limited Entry: The condition elements in the limited entry decision tables can only be binary values.

 

2. Extended Entry: The condition entries in the extended entry decision table have more than two values. Extended entry decision tables are those that use numerous conditions and various outcomes for each condition rather than just true or false.

 

Also Read | Key Steps for Vulnerability Testing

---

Different Black Box Testing Techniques

---

Applicability of Decision tables:

 

1. The resulting action is independent of the sequence in which the rules are evaluated.

2. Only at the unit level can the decision tables be used with ease.

3. After a rule is met and action is chosen, another rule needs to be looked at.

4. The limitations do not completely preclude many applications.

 

Advantages Of Decision Table Testing:

 

1. One of the best and most complete methods for design testing is the use of decision tables.

 

2. Decision table testing allows testers to examine the outcomes of various input configurations and software states.

 

3. It allows developers to specify and examine intricate business rules.

 

4. The most popular black box testing and requirements management method is decision table testing.

 

5. Complex business logic is modeled using a decision table. Through decision table testing, they can first be transformed into test cases and test scenarios.

 

6. This method offers thorough coverage of all test cases, which can considerably save the amount of rewriting required for test cases and test scenarios.

 

7. The completeness attribute of decision tables ensures that all conceivable combinations of condition values are covered.

 

8. Iterative usage of decision tables is possible. The first testing iteration's table findings can be used for the second and so on.

 

9. Decision tables are simple to comprehend, and anyone without prior knowledge may utilize and implement this design and testing process, scenarios, and test cases.

 

10.  Both developers and testers can examine and analyze several conditions, scenarios, and results on the same page.

 

Also Read | Step by Step Guide for Usability Testing

 

Disadvantages of Decision Table Testing:

 

We've noticed that decision table testing is really helpful when we need to test intricate business rules. We should be aware of the decision table's potential hazards, just like with any other technique.

 

1. Taking Note of Every Combination and Action - 

 

First off, making sure we have recorded all possible input combinations and actions might be difficult. In huge systems, there are a variety of combinations that are simple to overlook. 

 

Additionally, we must keep in mind that the effectiveness of the decision table exclusively depends on our capacity to accurately record these combinations.

 

2. Redundant Combinations -

 

Second, if we only rely on the permutations, the decision table might also introduce redundant combinations.

 

Also Read | What is the Quality of Service (QoS)?

 

How do you make a decision table for software testing?

 

The Decision Table is another software testing tool that is frequently used to assess how the system will behave given various input combinations. The Decision Table is produced using a logical diagramming method known as cause-effect graphing, which explains why it is called the cause-effect table. 

 

Because of this, it can be employed effectively when the behavior of the software depends on a lot of logical choices. It's important to note that black box testing methodologies are applicable at all test levels (Component Testing, Component Integration Testing, System Testing, and Unit Testing).

 

When it comes to Decision Table Testing, there are a few key guidelines to remember:

 

1. It is necessary to fill in any knowledge gaps about the system requirements, and the tester should make sure that the specifications are thorough enough to permit the effective development of a black-box test case.

 

2. Writing Test Cases: Writing test cases that are sufficiently effective at finding flaws is the most challenging component (remember, we don't know the internal design!).

 

3. Happy Paths: These are crucial business situations where we offer encouragement. The steps that are encountered the most frequently are found on pleasant paths. For instance, I will be able to log in successfully if I enter a legitimate username and password.

 

4. Alternative Plans of Action: These are complex business situations with advantageous inputs. These aren't the methods that are employed the most often, though. For instance, if my session doesn't end, I should be able to log in automatically without having to input my username and password again!

 

5. Negative Paths: In these business scenarios, we enter negative data and anticipate that the system will produce an error message—of course, a polite one!

 

6. Modification: We need to modify our execution to put more emphasis on the trouble spots. We also examine the test coverage we have and the methods for which we are unable to uncover bugs.

 

7. Defects Logging and Closure: The last step is to log the flaws and, once they have been fixed, retest them.

 

Also Read |  Grid Computing: Types, Components, and Applications

 

How is Software testing improved by the Decision Table?

 

As it should contain all circumstances, a well-designed Decision Table can help sort out the system's proper reaction based on the input data. It gives developers more control by enabling them to describe and interpret intricate business rules. Additionally, it streamlines the logic design procedure, which helps with the creation and testing of our product.

 

Anyone with no prior expertise can use and implement this design and testing process, scenarios, and test cases since decision tables are easy to understand. Project team members can immediately learn in-depth insights into the current problem through instructive examples and real-world scenarios.

 

End Note: The Purpose of Decision Table Testing:

 

Decision tables can easily balloon to gigantic sizes when dealing with complex data and ensuring that every potential combination has been considered. If you choose well, you can reduce the number of alternatives in each option to just choose the most interesting and important ones. This technique is known as collapsed decision table testing.

 

In this process, redundant criteria that have no bearing on the result are removed, and a variety of outputs are produced. An additional layer of analysis is added to the test design to help the tester conduct more efficient testing.

 

A reliable specification-based testing technique that may be applied in various situations is decision tables. All stakeholders and non-technical people can easily understand the tabular and graphical representations. Project team members can swiftly gain an in-depth understanding of the subject at hand through instructional examples and real-life circumstances. 

 

The information is easier to find than in the text describing the logic of the system because it is given in design tables in a clear, intelligible way. Finally, using this technique allows for the identification of the system's missing components and the detection of edge cases.