hibernate-hql
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<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.dialect">org.hibernate.dialect.MySQLInnoDBDialect</property>
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1��hql(hibernate query language) query
2��Criteria query
3��Native query
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public class HQLDao extends HiberanteUtils{
public static HQLDao getInstanse() {
return new HQLDao();
}
/**
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* @author Think
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*/
public List<Classess> queryAllClasses(){
Session session = sessionFactory.openSession();
List<Classess> cList = session.createQuery("from Classess").list();
session.close();
return cList;
}
public List queryClasses_Properties(){
Session session = sessionFactory.openSession();
List cList = session.createQuery("select cid,cname from Classess").list();
session.close();
return cList;
}
public List<Classess> queryClasses_Constructor(){
Session session = sessionFactory.openSession();
List<Classess> cList = session.createQuery("select new cn.itcast.domain.Classess(cname,description) from Classess").list();
session.close();
return cList;
}
public Classess queryClasses_Condition(){
Session session = sessionFactory.openSession();
Query query = session.createQuery("select new cn.itcast.domain.Classess(cname,description) from Classess where cid=:cid");
query.setLong("cid", 1L);
Classess classes = (Classess)query.uniqueResult();
System.out.println(classes.getCname());
session.close();
return classes;
}
public Classess queryClasses_Condition_2(){
Session session = sessionFactory.openSession();
Query query = session.createQuery("select new cn.itcast.domain.Classess(cname,description) from Classess where cid=?");
query.setLong(0, 1L);
Classess classes = (Classess)query.uniqueResult();
System.out.println(classes.getCname());
session.close();
return classes;
}
/**
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* @return
*/
/**
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*/
public void queryClasses_SubSelect(){
Session session = sessionFactory.openSession();
List<Classess> cList = session.createQuery("from Classess where cid in(select cid from Classess where cid in(1,2,3))").list();
session.close();
}
public static HQLDao getInstance(){
return new HQLDao();
}
/*********************************************************************************************/
/**
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public List<Classess> queryClasses_Student_EQ(){
Session session = sessionFactory.openSession();
List<Classess> cList = session.createQuery("from Classess c,Student s where c.cid=s.classess.cid").list();
session.close();
return cList;
}
/**
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* @return
*/
public List<Classess> queryClasses_Student_INNER(){
Session session = sessionFactory.openSession();
List<Classess> cList = session.createQuery("from Classess c inner join c.students").list();
session.close();
return cList;
}
/**
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* @return
*/
public List<Classess> queryClasses_Student_INNER_FETCH(){
Session session = sessionFactory.openSession();
List<Classess> cList = session.createQuery("from Classess c inner join fetch c.students").list();
session.close();
return cList;
}
/**
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*/
public List<Classess> queryClasses_Student_LeftJoin(){
Session session = sessionFactory.openSession();
List<Classess> cList = session.createQuery("from Classess c left outer join c.students").list();
session.close();
return cList;
}
/**
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*/
public List<Classess> queryClasses_Student_LeftJoin_fetch(){
Session session = sessionFactory.openSession();
String hql = "from Classess c left outer join fetch c.students";
hql = "from Student s left outer join fetch s.classess c";
List<Classess> cList = session.createQuery(hql).list();
session.close();
return cList;
}
/**
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*/
//public List<Classess> queryClasses_Student_Select(){
//Session session = sessionFactory.openSession();
//String hql = "select new cn.itcast.domain.ClassesView(c.cname,s.sname) " +
// "from Student s left outer join s.classes c";
//List<Classess> cList = session.createQuery(hql).list();
//session.close();
//return cList;
//}
/**
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*/
public void testQueryCourse_Student(){
Session session = sessionFactory.openSession();
List<Student> studentList = session.createQuery("from Student s inner join fetch s.courses c").list();
session.close();
}
/**
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*/
public List<Student> queryClasses_Student_Course(){
Session session = sessionFactory.openSession();
String hql = "from Classes cs inner join fetch cs.students s inner join fetch s.courses c";
hql = "from Student s inner join fetch s.classes cs inner join fetch s.courses c";
//hql = "from Classes cs left outer join fetch cs.students s left outer join fetch s.courses c";
List<Student> cList = session.createQuery(hql).list();
//Set<Classes> cset = new HashSet<Classes>(cList);
//cList = new ArrayList<Classes>(cset);
System.out.println(cList.size());
//for(Classes classes:cList){
//System.out.println(classes.getCid());
//Set<Student> students = classes.getStudents();
//for(Student student:students){
//System.out.println(student.getSname());
//Set<Course> courses = student.getCourses();
//for(Course course:courses){
//System.out.println(course.getCname());
//}
//}
//}
session.close();
return cList;
}
}