Exploring Decision Tables for Software Testing

For this week’s blog post, I decided to choose a subject that would give me a little more experience with a technique for black box testing, or developing tests for software without direct access for the code for a particular application. This way, the tests are created with a bigger focus on the business logic instead of particular barriers that may arise within a programming language or the overall stack of the application. I found an article on softwaretestingclass.com that covers the usefulness of decision tables in regards to software testing. The article discusses how to use decision tables as well as why they are such an important tool for black box testing. The article also mentions other examples of testing techniques for black box testing.

The author, Venktesh Somapalli, provides an example of a financial application where there are two possible conditions for a user, repayment within a term, or moving on to the next term of a loan. Somapalli goes through the steps that a tester may consider constructing a decision table for this particular application. The table for the decision table technique is based on conditions either being true or false, so all outcomes are absolute. This means that there are there should only be one outcome for a set of conditions. However, the reverse of this is not true, there are can be more than one set of conditions that have a particular outcome. In the example in the article, if both of the conditions are true or false, an error message is the outcome. On the other hand, there is only one set of conditions that processes money, and one that processes the loan term.

My favorite part of this testing technique is that it is inherently non technical due to the nature of black box testing and the simplicity of the concept. This means that non technical people within a business can understand and even develop test cases using this technique. As Somapalli points out, this technique is also versatile because it can be applied to any set of business logic. Somapalli also notes that decision tables are iterative meaning that if any new conditions are added to the logic, the existing table can be reused and revised to consider the new logic without a complete reconstruction. I definitely agree with his arguments for the usefulness for this technique. I have used this technique in the past and before reading this article, I didn’t even consider the powerful nature of this versatile strategy. I will definitely continue to make use of this technique when developing test cases whenever possible throughout my career.

Link to the original article: https://www.softwaretestingclass.com/what-is-decision-table-in-software-testing-with-example/

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