Performance — performance optimization, benchmarking, and profiling in Java applications
This article has been merged into the fuller Hibernate 7 stored procedures guide, which covers @NamedStoredProcedureQuery, StoredProcedureQuery and ProcedureCall together — and, unlike either original, actually executes the procedures it describes.
@Immutable is a pure marker annotation that skips Hibernate's dirty-checking snapshot -- mutate a field and flush, and nothing happens: no UPDATE, no exception, just silent data loss of the in-memory change. This rewrite runs every claim against Hibernate 7.4.5 -- entity mutation, bulk HQL (rejected at translation time by default, a correction neither prior version made), collection mutation, @Immutable+@Version, and a real flush-cost measurement -- and compares the annotation head-to-head with Session.setReadOnly().
Verified against Hibernate 7.4.5: a repeat bySimpleNaturalId lookup in the same session costs zero extra queries with no cache at all, but the bigger correction is that @NaturalIdCache populates its L2 region at insert time, not on first lookup -- so the textbook miss-then-hit story only applies to rows Hibernate didn't insert itself.