Decision Table Testing

What is a Decision Table

It is a table that shows different combination inputs with their associated outputs; this is also known as a cause-effect table.

In EP and BVA, we have seen that these techniques can be applied to only specific conditions or inputs; however, if we have different inputs that result in different actions being taken, or in other words, we have a business rule to test where there are various combinations of inputs which result in different actions.

For testing such rules or logic decision table testing is used.

It is a black box test design technique.

Parts of Decision Tables :

In software testing, the decision table 4 parts, which are divided into portions and are given below :

1. Condition Stubs: The conditions are listed in the first upper left part of the decision table to determine a particular action or set of actions.
2. Action Stubs: All possible actions are given in the decision table’s first lower left portion (i.e., below the condition stub).
3. Condition Entries: In the condition entry, the values are inputted in the upper right portion of the decision table. In the condition entries part of the table, multiple rows and columns are known as Rule.
4. Action Entries:  In the action entry, every entry has some associated action or set of actions in the lower right portion of the decision table, and these values are called outputs.

Types of Decision Tables :

The decision tables are categorized into two types, and these are given below:

1. Limited Entry: The condition entries are restricted to binary values in the narrow entry decision tables.
2. Extended Entry: The comprehensive entry decision table condition entries have more than two values. The decision tables use multiple conditions where a condition may have many possibilities instead of only ‘true’ and ‘false,’ known as extended entry decision tables.

Applicability of Decision Tables :

• The order of rule evaluation does not affect the resulting action.
• The decision tables can be applied easily at the unit level only.
• Once a rule is satisfied and the action selected, another rule needs to be examined.
• The restrictions only eliminate a few applications.