Reading/Creating/Updating Object Reference Type Attributes
When you create an Object Reference type of attribute for a Department Data or Extended Data object, an Object Reference navigation property is added in the metadata response of the domain. The suffix Nav is added to the Object Reference structural property name to form the Object Reference navigation property name. For example, if you create the Object Reference type attribute SupplierPart for a Department Data object, then the Object Reference navigation property name is SupplierPartNav. The Object Reference navigation property always points to the PTC.ObjectReferenceable Type.
You can read, set, or update Object Reference type of attribute values using the Object Reference navigation property while retrieving, creating or updating Department Data objects, Extended Data objects, or their subtypes.
This example shows you how you can create two Department Data objects for a Plant Data object with required and other attributes. This example also shows you how to create one of the Department Data objects along with an Object Reference type attribute SupplierPartNav for a Part. Use the following POST URI with the request body.
URI
POST /Windchill/servlet/odata/BomTransformation/CreateDepartmentDataForPlantData?$expand=DepartmentData
* 
You must apply $expand on DepartmentData, otherwise an empty list is returned.
Request Headers
Content-Type: application/json
CSRF_NONCE: <Use the value from Fetch NONCE example>
Request Body
{
"plantData": [
{
"ID": "OR:com.ptc.windchill.enterprise.data.EnterpriseData:200886"
}
],
"departmentData": [
{
"@odata.type": "#PTC.BomTransformation.Logistics",
"Category": "process",
"Location": "004",
"SupplyChain": "005",
"SupplierPartNav@odata.bind": "Parts(OR.wt.part.WTPart:204755)"
},
{
"@odata.type": "#PTC.BomTransformation.Logistics",
"Category": "procurement",
"Location": "003",
"SupplyChain": "001"
}
]
}
In this example, the request creates two Departments Data objects for the Plant object. For one of the created Department Data objects, the response also shows the defined custom attribute that the custom logic uses to navigate to the Object Reference type attribute value set in the request. The request creates the Part object specified in the Object Reference type attribute value and you can navigate to the Part object from the value of the custom attribute.
URI with Expand on the Navigation Property
GET /Windchill/servlet/odata/BomTransformation/GetDepartmentDatas?$expand=SupplierPartNav