Spring Data JPA save() with application-assigned vs generated ids. Spring Boot parent 4.1.1, Hibernate 7.4.14.Final, H2

== AssignedBook: UUID.randomUUID() assigned in the constructor, no @Version
   sql> select ab1_0.id,ab1_0.title from assigned_book ab1_0 where ab1_0.id=?
   sql> insert into assigned_book (title,id) values (?,?)

== VersionedBook: same, plus a boxed @Version column
   sql> insert into versioned_book (title,version,id) values (?,?,?)

== PersistableBook: same, entity implements Persistable.isNew()
   sql> insert into persistable_book (title,id) values (?,?)

== GeneratedBook: @UuidGenerator(style = VERSION_7), id is null until persist
   sql> insert into generated_book (title,id) values (?,?)

== saveAll of 100 new AssignedBook rows: selects issued
select statements : 100, insert statements : 100

== saveAll of 100 new GeneratedBook rows: selects issued
select statements : 0, insert statements : 100