jpa用原生SQL查询数据库

public class EntityManagerDAO { @PersistenceContext private EntityManager entityManager; @Transactional public List<StudentTeacherDTO> list(){ String sql = "select a.id as id, a.name as studentName, b.name as teacherName, a.grade as grade, b.course as course from student as a, teacher as b where a.id = b.id"; SQLQuery sqlQuery = entityManager.createNativeQuery(sql).unwrap(SQLQuery.class); Query query = sqlQuery.setResultTransformer(Transformers.aliasToBean(StudentTeacherDTO.class)); List<StudentTeacherDTO> list = query.getResultList(); entityManager.clear(); return list; } @Transactional public List<StudentTeacherDTO> list1(){ String sql = "select a.id as id, a.name as studentName, b.name as teacherName, a.grade as grade, b.course as course from student as a, teacher as b where a.id = b.id"; Query nativeQuery = entityManager.createNativeQuery(sql, StudentTeacherDTO.class); List<StudentTeacherDTO> list = nativeQuery.getResultList(); entityManager.clear(); return list; } }