复合主键的查询方法

 

映射文件都是eclipse自动生成,包括Users.java 和 UserPK.java。 这边就不贴出来了

假如USERS表的主键为NAME字段,TEL字段和AGE字段,那么在User类中也应该存在相对应的属性和方法,映射方法如下:


 "-//Hibernate/Hibernate Mapping DTD//EN"
 "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd" >


   name="Users"
  table="USERS"
 >
  false
  
       name="name"
    column="NAME"
    type="string"
   />
       name="tel"
    column="TEL"
    type="string"
   />
  

     name="age"
   column="AGE"
   type="string"
   not-null="false"
  />
  
  


以下代码生成一个Users对象,并保存.

    Session s = HibernateUtil.currentSession();
    Transaction t = s.beginTransaction();
    UsersPK usersPK = new UsersPK();
    usersPK.setName(1);
    usersPK.setTel(4);
    Users user = new Users();
    user.setAge("19");
    user.setId(usersPK );
    s.save(user);
    t.commit();
    HibernateUtil.closeSession();
    System.out.println("insert success!");

更新.

    Session s = HibernateUtil.currentSession();
    Transaction t = s.beginTransaction();
    UsersPK usersPK = new UsersPK();
    usersPK.setDbid(1);
    usersPK.setRowUID(4);
    Users user = (Users)s.load(Users.class, usersPK);

    user.setAge("20");
    s.update(user);
    t.commit();
    HibernateUtil.closeSession();
    System.out.println("update success!");

删除.

Session s = HibernateUtil.currentSession();
    Transaction t = s.beginTransaction();
    UsersPK usersPK = new UsersPK();
    usersPK.setDbid(1);
    usersPK.setRowUID(4);
    Users user = (Users)s.load(Users.class, usersPK);

    s.delete(user);
    t.commit();
    HibernateUtil.closeSession();
    System.out.println("delete success!");

最后讲select

如果对复合主键中的一个主键进行查询,必须

    Session s = HibernateUtil.currentSession();
    Criteria c = s.createCriteria(Users.class);
    c.add(Restrictions.eq("id.name", "levi"));
    List list = c.list();
    Iterator iter = list.iterator();
    while (iter.hasNext()) {
      Users item = (Users) iter.next();
      System.out.println("name:" + item.getId().getName());
      System.out.println("tel;" + item.getId().getTel());
      System.out.println("age:" + item.getAge());
    }
    HibernateUtil.closeSession();
    System.out.println("select success!");

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