Create spring repository without entity

CrudRepository or JpaRepository were not designed to work without an <Entity,ID> pair.

You are better off creating a custom repo, inject EntityManager and query from there:

  @Repository
  public class CustomNativeRepositoryImpl implements CustomNativeRepository {

    @Autowired
    private EntityManager entityManager;

    @Override
    public Object runNativeQuery() {
        entityManager.createNativeQuery("myNativeQuery")
         .getSingleResult();
    }
}