Hibernate: Pagination with join fetch loads everything into memory

A join multiplies rows, so Hibernate cannot page in SQL and warns before doing it in Java instead.

Code

// Dangerous:
@Query("select o from Order o join fetch o.items")
Page<Order> paged(Pageable pageable);

Output

WARN HHH90003004: firstResult/maxResults specified with collection fetch;
applying in memory

Fix: page the ids first, then fetch the items for that page.

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Published 2026-08-11