When the following propert is set in persistence.xml to a value greater than 1

<property name="hibernate.default_batch_fetch_size" value="2" />

Then,

In a graph with a Parent-Child relationship, where the Child has a @ManyToOne to Parent entity, with default fetch EAGER. Then when hibernate-test-case-eager-regression.zip Child entities are loaded by an HQL query using the resultStream method, the parent entity is not mapped on any of the elements returned to the stream.

See attached test case proving the way it worked in Hibernate 5, and the subsequent fault in 6.

Workaround 1: Switch to @ManyToOne(fetch=FetchType.LAZY)