Required versus Optional Dependents
In Windchill Workgroup Manager, explicit meaning is assigned to the two types of dependent relationships, required and optional. Required has two meanings:
The dependent is required to completely define the set of interrelationships between objects in Windchill.
The dependent is necessary for successful retrieval of the object in NX.
Optional means that the dependent is not necessary for successful retrieval of the object in NX. For example, a suppressed component is optional in an assembly (in general, the only optional members of an assembly are suppressed components). However, if the component is resumed, it becomes a required dependent.
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Whether a dependent is required or optional can depend on the configuration retrieved from Windchill. Also be aware that you are not prevented from removing a required assembly member from the list of objects being retrieved; however, removing a required member may require your intervention in NX to complete retrieval.
In the case when NX provides you a choice whether to retrieve related objects, these are optional dependents.
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