Integrations (PTC products, 3rd party products and code) > 3rd party product integrations (CM, DOORS, Rose, Simulink and XML) > Configuration management tool integration > Typical lifecycle of a model stored in a CM tool (CM tool integration) > Understanding stubs (CM tool integration)
  
Understanding stubs (CM tool integration)
Create replica, get latest and check out operations can result in the creation of stubs. When a Model, Package or item is created as a stub, it has the following characteristics:
In the Modeler panes, its icon includes this symbol: (except for the Model).
When selected, STUB is displayed in the Modeler Status Bar.
Its properties are not fully populated, for example, the Description property will be blank.
It is read-only, irrespective of what access permissions you have to it.
Links to other items may not be included.
Stub items (except the Model or Packages) are not displayed in the Packages pane.
If you perform a get latest or check out operation on a stub Model, Package or dictionary item (through its Package):
Its properties are fully populated.
It is no longer read-only. Note that a get latest operation will not result in the item being editable.
Links to other items are included.
Modeler creates stubs to minimize the time taken to perform create replica, get latest and check out operations. Without stubs, you would spend a lot of time updating Packages with information you did not require. Stubs also ensure that the Package hierarchy is maintained.
Tip: To find stubs in the model: in the Packages pane, right-click the Model, point to Find, and then click All Model Stubs (to find all stubs) or Unused Stubs (to find stubs that are not used by other items or diagrams).
The Model is created as a stub during the following operation:
Create Replica: The Model is created as a stub. The items it directly scopes are not created in the model.
A Package can be created as a stub during the following operations:
Create Replica: Each Package is created as a stub. The items scoped by each Package are not created in the model.
Get Latest: If the Get New Packages check box is cleared and there are sub-Packages in the CM tool Model that are not present in the Modeler Model, those sub-Packages are created as stubs.
Check Out: If the Checkout New Packages check box is cleared and there are sub-Packages in the CM tool Model that are not present in the Modeler Model, those sub-Packages are created as stubs.
An Item can be created as a stub during the following operations:
Get Latest: If the Get Latest operation gets a Model, Package or item that references an item that is not in the Modeler model, that referenced item is created as a stub.
Check Out: If the Check Out operation checks out a Model, Package or item that references an item that is not in the Modeler model, that referenced item is created as a stub.
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When a stub item is created in a model, it may be scoped by the Model rather than the Package that should scope it.