Hibernate: A managed entity is saved without calling save()

Dirty checking flushes changes at commit. Calling save() on a managed entity is a no-op people add out of habit.

Code

@Transactional
public void rename(Long id, String name) {
    Order o = repo.findById(id).orElseThrow();
    o.setName(name);          // that is all
    // repo.save(o);          // unnecessary - it is already managed
}

Output

Hibernate: update orders set name=? where id=?
Issued at commit, by dirty checking, whether or not save() was called.

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Published 2026-08-11