A query selecting a relationship field does not include null in the query result.

A query selecting a relationship field does not include null in the query result when the value of the relationship field is null. This entry is instead skipped from the query result; for example:

SELECT o.customer FROM Order o WHERE ...

See https://glassfish.dev.java.net/issues/show_bug.cgi?id=637 for more information.

Solution

Select a state field from the related instance.

SELECT o.customer.customerId FROM Order o WHERE ...