Constraints

Enumeration Constraints

Enumeration Constraints are used to restrict the possible values of a Property in the context of a class.

In some cases Properties shall be used as filter criteria as well as a property of an Application Class (especially Properties with a Value list).
If such a Property is used as a filter criteria, then all values from its value list shall be offered for selection (independent from the different Application Classes, in which the property is used).
If the same Property is used in an Application Class, then the Application Class has already been selected and only some of the values of the property are suitable for this Application Class. Therefore a constraint of the list of values is necessary: only the suitable values shall be offered for selection for a specific Application Class.

Example 1: A customer knows a product name but does not know the related Application Class. He expects that he can enter the product name as filter criteria and gets all assets with this product name as result (and implicitly, he also expects to get the corresponding Application Class).

Example 2: An expert wants to enter a missing asset. He expects that only product names are offered which are suitable to the already selected Application Class.

Create Enumeration Constraint

Enumeration Constraints can be created via the Restrict Value List functionality.

The workspace area for the management of Constraints can be accessed via menu Constraints. The workspace area consists of the list of available constraints and button Restrict value list. Information on the graphical user interface and basic functionalities can be found on page Graphical User Interface and Basic Functions.

The workspace area for the management of Constraints offers users the possibility of creating enumeration constrains via functionality Restrict value list.

After pressing the button Restrict value list, the system displays the tree view of classes. Starting point for the creation of enumeration constraints is a Property (with Value List) used in context of a specific Class.

After selection of the Property the system displays the Create Constraint graphical user interface which consists of:

• the details page of the selected Property

• the details page of the Class in which the selected property is used 

• the list of all Values in the Value List connected to the selected Property

The user can select from the list of values the ones which will remain valid in the context of the specific Class. 

After defining the allowed values. the user may confirm the constrained values via button Save or Save and Release.

On Save, Change Request of type Enable Value will be created. Change Requests usually undergo an approval process before they are released and become effective. 

On Save and Release, the Change Request of type Enable Value will be automatically executed (released). As a result, the constrained values are offered for the Property in the context of respective specific Class.

Remove Enumeration Constraint

The removal of constrains can be also performed using the functionality Restrict value list. If for the Property selected in the tree view constraints already exists, they will be displayed in the Create Constraint graphical user interface as values with a checked selection box in front of them. In order to remove an existing Constraint, user has to uncheck the check-box in front of respective Value, then confirm the changes via Save or Save and Release.

On Save, Change Request of type Remove Constraint will be created. Change Requests usually undergo an approval process before they are released and become effective. 

On Save and Release, the Change Request of type Remove Constraint will be automatically executed (released). As a result, the value will be removed from the list of allowed Values for respective Property in the context of a given class. 

Range Constraints

Range Constraints are used to define a range (minimum/maximal value) for the possible values of a Property.

Create Range Constraints

This functionality is available in all classes lists (Application Classes, Blocks and Aspects). It allows users to define range (min/max) constraints for Integer (count) and Real (count) properties used within a Class. 

e.g. In case of cardinality structures used in the context of a specific Application Class, the customer wants to restrict the possible valuations of a block by defining a specific range (e.g. for a car, the number of doors can be for example minimum 2 and maximum 5). 

After pressing the button (Create Range Constraint), the system displays the tree view of classes. Starting point for the creation of range constraints is a Property with datatype Integer (count) and Real (count). 

After selection of the Property the system displays the Create Range Constraint graphical user interface which consists of:

• the details page of the selected Property

• the details page of the Class in which the selected property is used 

• field for entering the Minimum Value for the Property

• field for entering the Maximum Value for the Property

After filling in the desired minimum and maximum Value and entering a Reason, the user may confirm the entered value range via button Save or Save and Release.

On Save, Change Request of type New Range Constraint will be created. Change Requests usually undergo an approval process before they are released and become effective. 

On Save and Release, the Change Request of type New Range Constraint will be automatically executed (released). As a result, the minimum and maximum values are displayed in brackets beside the name of the Property.