Hibernate: The first-level cache is the persistence context

Within one transaction, loading the same id twice hits the database once - and returns the identical object.

Code

@Transactional
void demo() {
    Order a = em.find(Order.class, 1L);   // SELECT
    Order b = em.find(Order.class, 1L);   // no SQL
    System.out.println(a == b);
}

Output

Hibernate: select ... from orders where id=?
true

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Published 2026-08-11