RESTful Java Web Services - Third Edition

Relationship operations

OData supports the linking of related resources. Relationships from one entity to another are represented as navigation properties. The following API reads employees in the HR department:

http://localhost:8080/hrapp/odata/Departments("HR")/   EmployeeDetails

The OData service even allows you to add, update, and remove a relation via navigation properties. The following example shows how you can use the navigation properties to link the employee with the id value of 1700 to the IT department:

POST odata/Departments('IT')/Employees/$ref 
OData-Version: 4.0 
Content-Type: application/json;odata.metadata=minimal 
Accept: application/json 
{ 
  "@odata.id": "odata/Employees(1700)" 
} 

Many API vendors have started considering OData ...