Hibernate hibernate query language(多对多一对多)

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public class MoreToMoreTest  extends HibernateUtil {    /**     *  迫切内连接 多对多     *  # 多对多 内连接     SELECT  c.*,s.* FROM Course c INNER JOIN student_course sc     ON c.cid = sc.cid INNER JOIN Student s ON sc.sid = s.sid     * */    @Test    public void testQueryCoursesAndStudents_InnerJoin_Fetch(){        Session session=sessionFactory.openSession();        List<Student> students=session.createQuery("from  com.sanmao.doubutils.Student s " +                "inner join fetch s.courses c").list();        System.out.println(students.size());        session.close();    }/** * 左外连接也一样,所以在hql 一对多和多对多的写法是一样的 * */    @Test    public void testQueryCoursesAndStudents_LeftOuterJoin_Fetch(){        Session session=sessionFactory.openSession();        List<Student> students=session.createQuery("from  com.sanmao.doubutils.Student s " +                "left outer join fetch s.courses c").list();        System.out.println(students.size());        session.close();    }}

public class OneMoreToMoreTest extends HibernateUtil {    /**     * SELECT c.*,s.*,cc.* FROM Classes c INNER JOIN Student     * s ON c.cid = s.cid INNER JOIN Course cc ON s.cid=cc.cid*/    @Test    public void testQueryClassesAndStudentAndCourses(){        Session session=sessionFactory.openSession();        List<Classes> classes=session.createQuery("from com.sanmao.onemanyutils.Classes c " +                "inner join fetch c.students s inner join fetch " +                "s.courses cc").list();        System.out.println(classes.size());        session.close();    }}

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