The JPQL select new syntax originated in the earliest days of Hibernate, providing a way to package a query projection list into a Java object.
This was before Java had generics or record types, so you would use it like this:

Hibernate Blog

Hibernate 6 introduced a cleaner alternative to the legacy JPQL `select new` syntax. Instead of embedding the constructor call in the query string, you can now pass the result type directly to `createQuery()` and Hibernate infers the mapping automatically. This works with Java records and also in Hibernate Data Repositories via the `@Query` annotation. The author notes this improvement is still underused and plans to standardize it in Jakarta Persistence 4, with a version already included in Jakarta Data 1.1.

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