Types of Decision Table

There are three types of Decision Tables. These are:

§  Limited Entry Table

§  Mixed Entry Table

§  Extended Entry Table

Limited Entry Table:

·         In Limited Entry Table, The condition and action statements are complete.

·         The condition and action entries are defined in limited manner like Y/N.


Mixed Entry Table:

·         In Mixed Entry Table, Some conditions and some action statements are complete and some are not complete.

·         The complete condition and action entries are defined with Y/N. Whereas, Incomplete condition and action entries are completed with full description in the entries.


Extended Entry Table:

·         In Extended Entry Table, all the conditions are some action statements are not complete.

·         The conditions and actions entries are completed with full description in the entries.


Advantages of Decision Table

§  It is easier to construct a decision table than flowchart.

§  Decision Table gives better representation of any solution of particular problem.

§  Decision Table is compact and easily understood.

§  Decision Table is very effective way of communication between analysts or programmer and non-technical users.

§  Decision Table provides a framework for complete and accurate statements of decision logics for any problem.

§  It forces programmer to think for all possible conditions and their actions for any problem.

§  It is possible to convert a decision table directly into a computer program with the help of specialized software.

§  With Decision Table it is possible to check that all the possible combination for answering has been considered.

§  Decision Table uses a standardized format.

§  Complex Table can be easily split into simple tables.

§  Table Solution is like a show cause and effect relationships.

§  To understand table no prior knowledge of computer is required.

Disadvantages of Decision Table

§  Decision Table cannot represent the clear sequencing of a problem as represented by flowcharts.

§  Decision Table are used for problem which involves logical sequencing. It is difficult to construct table for problem involving various arithmetic calculations.

§  For a simple logical problem, Flow charts serve the better purpose than decision tables.