Spring-data-jpa, as you’re saying, offers more that just the classical Spring-JPA integration. With JPA/Hibernate integration, you get mainly
- declarative transaction management using JPA/Hibernate transactions
- exception translation
- the JPA EntityManager or the Hibernate SessionFactory as injectable beans
With Spring-data-jpa, you get all that, plus (among other things)
- interface-only repositories, using method names to infer queries automatically
- @Query annotation to define the query that an interface method should return
- automatic handling of Pageable queries
- base classes for standard crud repositories
This is just a tiny introduction. For more help, read the documentation.