Partial object query that leaves out an association to avoid loading it fetches the association anyway.

Assuming:

Customer <onetoone> Cart

where Cart is the owning side.

Since the association from Customer to Cart can not be lazy, it would make sense to leave out the association in a query to avoid loading the carts like this:

select partial c.{id,name, ... anything except cart} from Customer c"

But this is ignored and the carts of all customers are fetched anyway. Query::HINT_FORCE_PARTIAL_LOAD is an alternative solution, however it has the disadvantage that it disables lazy-loading for all queried objects. If partial querying would honor associations this would allow more fine-grained control.