Whenever an element class of an aggregate has its own field for the ID that is also used as keyColumn for the one-to-many relationship to its aggregate root, access to these elements will cause duplicated columns in the generated SQL and consequently warnings like:

ResultSet contains id multiple times

The problem is described in detail in this StackOverflow question.

Here is a small project repo to demonstrate the problem.

Desired behaviour: No warnings, the column accesses should probably be "squashed".