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 Autodesk Inventor.
Optional means that the dependent is not necessary for successful retrieval of the object in Autodesk Inventor. 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 the Autodesk Inventor session to complete retrieval.
Consider the following case:
1.ipt is a part model.
2.ipt is a part model. Its only feature is derived from 1.ipt.
Both models are checked in to Windchill.
The user checks out 2.ipt, but excludes 1.ipt from the collection.
On retrieval, 2.ipt throws an exception in Inventor, stating that 1.ipt is not found, and the link must be resolved in order to successfully retrieve.
This demonstrates a required dependency.
In the case when Autodesk Inventor provides you a choice whether to retrieve related objects, these are optional dependents.
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