Chapter 6 Managing Objects
In PowerDesigner, objects have identifying properties. Identifying properties are used to control object uniqueness in the model or package namespace.
The namespace defines an area in which the name and the code of an object of a given type must be unique.
For more information on the management of namespace, see section Managing the namespace in models in chapter Managing Models.
In PowerDesigner, each package can be a namespace. It is however possible to expand the namespace to the parent of a given package. You can cascade the expansion until you reach the level of the model itself.
Objects that appear in the Model Explorer tree view obey to the general rules that follow:
In Model Explorer tree view | Namespace | Uniqueness rule |
---|---|---|
Objects directly under a package or a model node (table, process, class) | Model | Unique name and code in model |
Package | Unique name and code in package | |
Objects under parent object (column, attribute) | Not applicable | Unique name and code in parent |
Linking objects (reference, relationship) | Not applicable | Unique name and code between same end objects (i.e., parallel links with same name and code are not allowed between same end objects) |
However, you may encounter some exceptions to those rules. For example only the code of a reference allows to identify the object in the entire model, when the "Unique code" option is selected in the Model Options dialog box. PowerDesigner warns you when a general rule is not respected.
For more information on the Unique code option, see the corresponding section in the appropriate User's Guide.
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