REST - Using $select always returns the primary key fields and $orderby fields in the response

[severussundar]

For the below GET request ,

GET https://localhost:5001/api/Book?$select=title

the response contains the id field as well.

Response:

{
    "value": [
        {
            "title": "New title #1",
            "id": 1
        },
        {
            "title": "Also Awesome book",
            "id": 2
        },
        {
            "title": "Great wall of china explained",
            "id": 3
        },
        ...
    ]
}

For the below GET request ,

GET https://localhost:5001/api/Book?$select=id,publisher_id&$orderby=name

the response contains the name field as well.

Response:

{
    "value": [
        {
            "id": 2,
            "publisher_id": 1234,
            "name": "Also Awesome book"
        },
       ...
       ]
}    

[severussundar]

As per OData Specs, only the fields requested in the $select clause should be returned in the response.

OData Specs Link

https://services.odata.org/OData/OData.svc/Products?$select=Price,Name
In a response from an OData service, only the Price and Name Property values are returned for each Product Entry within the Collection of products identified.
If the $select query option had listed a Property that identified a Complex Type, then all Properties defined on the Complex Type must be returned.