Skip to end of metadata
Go to start of metadata

On this page:


Adding rules to a decision table

Once a decision table is attached to a decision or business knowledge model, you can specify the decision logic to that element. Initially, a decision table only contains one empty rule.

Add a rule for each possible scenario of a condition with its possible value and the result. The end result will be a decision table with all relevant scenarios for the decision logic.

To add a rule to a decision table, do as follows:

  • Select a rule, and then click to the left of the rule.


The new rule is added directly below the rule you selected.



A dash (─) is displayed if a condition cell is empty. This is the initial display of the column after adding a rule, but if it is left empty after the decision table has been filled, it means that the condition is irrelevant for that rule.

Setting the hit policy for a decision table

The hit policy of a decision table defines whether one or more rules may match for a given set of input data, and possibly about the order in which the rules should be executed. Hit policies can be divided in single-hit policies and multiple-hit policies.

The result of a multiple-hit policy is a list of values, which means that the conclusion information item of a decision table with such a policy should be a list information item. However, the "Collect" hit policy can also be used in combination with an aggregation operator, in which case the result is a single value. For an overview of the available hit policies, see Hit policies for decision table rules.

To set the hit policy for a decision table, follow these steps:

  1. In the decision table, click the hit policy cell, and then click the control.



  2. In the options list, select the hit policy of your choice.


The hit policy cell now shows the letter representing the chosen hit policy.

To close the options list without changing the value, click the control at the bottom of the list.

Adding conditions to a decision table

By default, a decision table contains the conditions derived from the structure of the model, but conditions can also be added to the table manually. To do this, follow these steps:

  1. Select the decision table title, and then click next to the title.



  2. In the selection window, select the decision or input data you want to add and click OK. If the decision table was generated from a business knowledge model, select an input parameter.


A new condition column is added to the right of the most right condition column in the table.


Add new condition

Instead of selecting an existing condition, you can also add a new one. To do this, click Cancel in the selection window instead of selecting a condition. Next, in the window that pops up, type the name of the new information item, and click OK.



The new information item is added to the decision table. If it is created in the decision table of a decision, the information item is also added as an input data to the glossary. In case of a business knowledge model, the information item is added as an input parameter to the glossary and to the business knowledge model in the decision requirements diagram.

Adding annotations to a decision table

A decision table may have multiple annotation columns, which may represent, for example different types of annotations. The annotation column heading specifies the annotation type.

If an annotation contains an information item name between < >, this will be replaced by the current value of the information item when displaying the annotation.

To add an annotation to a decision table, follow these steps:

  1. Select the decision table title, and then click next to the title. A new annotation column is added to the table.



  2. Click in a cell of the annotation column, type the text, and press Enter. Repeat this step for each cell you want to add information to.

Adding operators and operands to conditions and conclusion

The condition columns can be filled with an operator, literal value for an operand, or a value or expression. For an overview of the supported operators for conditions, see Operators for conditions in a decision table.

The conclusion column only has an operand, which specifies the result of each rule. In this column, a literal value for an operand can be selected, or a value or expression can be entered or edited free-format.

The keyword "EMPTY" (or a translation of it) or "NULL" can be used to explicitly check for empty input values or an empty list in a condition, in case of a list information item. Also, an "EMPTY" result can be specified in this way.


Decision table with an "EMPTY" condition and result

Using the control

To add an operator or literal value for an operand to a cell, follow these steps:

  1. In the condition or conclusion cell, click the control.

  2. Depending on the type of data of the cell, you:

    select an item in the available options list, for example:



    or enter data in the window that pops up, and click OK. Example:


Free-format editing

The content of a cell can also be entered or edited free-format by clicking in the cell and typing the text. In cells without the control, this is the only option.


Free-format editing in a condition column cell

Using expressions for conditions and conclusions

Both for the operand of a condition and for the conclusion, an expression may be used instead of a fixed value. In an expression, the following may be used:

  • numerical values
  • monetary values
  • string values
  • information item names
  • basic arithmetic operators (+, -, *, /)
  • logical operators for Booleans (&&, ||, !)
  • parentheses
  • list indexes ([..])

  • a number of predefined functions


For an overview of the supported functions, see Functions for expressions in conditions and conclusions in a decision table.

An expression is preceded by the = symbol. A single information item name is also considered to be an expression, and is also preceded by the = symbol. However, if only an information item name is entered, the = symbol will be inserted automatically.

The decision table below shows an example of the use of an expression in the operand of the conclusion.


Example of the use of an expression


To create an expression, do as follows:

  • In the decision table, click in a condition or conclusion cell, and add the desired information.

You can type the information manually, but also use the control to add operators and operands.

Using input parameters in an expression

If the decision table belongs to a business knowledge model, it is possible to use input parameters in an expression. If the business knowledge model already has input parameters attached, you can use them by simply including their names in the expression.

To see which parameters are already attached, just hover the table's control to see their names. These are the names you can use in the expression.


Available input parameters in a decision table


If the business knowledge model does not have input parameters yet, you can add them to the decision table. Once added to the decision table, the input parameters will also be attached to business knowledge model in the decision requirements diagram.

To add an input parameter to the decision table, follow these steps:

  1. Select the decision table title, and then click next to the title.



  2. In the Input Parameter Name window, type the name and click OK.


If you hover the control you will see the newly added parameter in the tooltip. Now you can include the input parameter in expressions.

Jumping from an information item to the related information item in the glossary

To directly jump from an information item in the decision table to the related information item in the glossary, do as follows:

  • Click the information item heading, and then click the control.


As a result, the glossary is opened with the information item row selected.