Chapter 2 Conceptual Data Model Basics

Domain and attribute

From the Attribute and Domain groupbox in Model Options, you can choose to enforce non-divergence between a domain definition and the attributes using the domain, for the following attribute properties:

Enforce non-divergence selected

In this mode, the selected attribute properties must be consistent with the domain properties.

When you apply the Enforce non-divergence options You are asked if you want to apply domain properties to attributes attached to the domain in the current model.

• If you accept to apply domain properties, the attribute properties are modified in order to be consistent with domain properties. However, if the check parameters, business rules, and mandatory value of an attribute are more constrained than those of the domain, these properties will not be modified. You may indeed need to define a shorter range of values in the attribute check parameters, or set an attribute as mandatory while the domain is not
• If you refuse to apply domain properties, the attribute is detached from the domain

When you modify the properties of a domain The properties of the attributes attached to the domain are updated provided these properties are selected in the Model Options dialog box.

Attributes cannot be modified When you select an attribute property under Enforce non-divergence, each instance of that attribute property in the lists of attributes and the property sheets of attributes appears grayed and can not be modified.

If you want to modify an attribute property that is defined as non-divergent, you must detach the attribute from its domain, or clear the Enforce non-divergence check box in Model Options.

Enforce non-divergence deselected

In this mode, it is still possible to select attribute properties under Enforce non-divergence.

If you select one or more of the attribute properties When you modify an attribute property so that it diverges from its current domain definition, you are asked if you want to keep the modifications and diverge from the domain.

If you do not select attribute properties When you modify an attribute or domain property resulting in a divergence, you are not warned, and you can no longer cascade the change on the attribute properties.

Default data type

In a CDM, you can select a Default data type to apply to domains and attributes if no data type is selected for them.

If you modify CDM options, these options apply only to the current CDM.

For information on other model options, see chapter Working with Models.

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