What Does Decision Table (DETAB) Mean?
A decision table is used to represent conditional logic by creating a list of tasks depicting business level rules. Decision tables can be used when there is a consistent number of conditions that must be evaluated and assigned a specific set of actions to be used when the conditions are finally met.
Decision tables are fairly similar to decision trees except for the fact that decision tables will always have the same number of conditions that need to be evaluated and actions that must be performed even if the set of branches being analyzed is resolved to true. A decision tree, on the other hand, can have one branch with more conditions that need to be evaluated than other branches on the tree.
Techopedia Explains Decision Table (DETAB)
The purpose of a decision table is to structure logic by generating rules derived from the data entered in the table itself. A decision table lists causes (business rule condition) and effects (business rule action and expected results), which are represented through the use of a matrix where each column represents a unique combination.
If there are rules within a business that can be expressed through the use of templates and data then a decision table is one technique that can be used to accomplish this. Each row of a decision table collects and stores its data separately and then combines the data with a specific or customized template to generate a rule. Decision tables should not be used if the rules in question do not follow a set of templates.