I don't know why the collection-valued navigation properties are always return an empty list with a reference to the actual data link.
here's the query I tried :
GET <organization>/api/data/v8.0/new_subjectareas?$expand=new_product_new_subjectarea&$count=true
Response :
{"@odata.context":"<organization>/api/data/v8.0/$metadata#new_subjectareas","@odata.count":150,"value":[
{"@odata.etag":"W/\"9644599\"","timezoneruleversionnumber":null,"processid":null,"_stageid_value":null,"new_product_new_subjectarea":[],"new_product_new_subjectarea@odata.nextLink":"<organization>/api/data/v8.0/new_subjectareas(622bcca9-8946-e511-80fb-00155d002810)/new_product_new_subjectarea"
},
....How can I get the items within the navigation property (new_product_new_subjectarea) without make a new request to it's reference (new_product_new_subjectarea@odata.nextLink)?