The four components of a decision table (condition stubs, condition entries, action stubs and action entries) are shown below.
Conditions to evaluate in a procedure are entered in the condition stub area of a decision table. Each condition stub entry is followed with a yes/no matrix in the condition entry area of the table. The yes/no matrix is used to represent all the possible true/false combinations of conditions in the table. You can also enter "-" (the hyphen character) in the cell to signify that you "don't care" if the condition's state is true or false.
Actions to perform under a set of true/false conditions are entered in the action stub area. A number in the action entry area identifies the action(s) to perform and in the required sequence.
The data in the condition entries together with the data in the action entries is read from top to bottom by column. The data grouped in each column is called a rule.