hibernate生成的sql语句的疑问？

[duanjianbo26]

在执行一个普通的查询，取某个持久化对象中5条记录时发现多了5条sql语句，请大侠指点！

查询dao的实现

 public List<UserFriend> findAll(User user, int begin, int number) {
    Session session = sessionFactory.openSession();
    try {
      session.beginTransaction();
      return session.createQuery("from UserFriend o where o.user=?")
          .setParameter(0, user).setFirstResult(begin).setMaxResults(number)
          .list();
    } finally {
      session.getTransaction().commit();
      session.close();
    }
  }

生成的语句为：

Hibernate: select userfriend0_.Id as Id2_, userfriend0_.userId as userId2_, userfriend0_.userIdFriend as userIdFr3_2_ from T_UserFriend userfriend0_ where userfriend0_.userId=? limit ?
Hibernate: select user0_.Id as Id1_0_, user0_.username as username1_0_, user0_.password as password1_0_ from T_User user0_ where user0_.Id=?
Hibernate: select user0_.Id as Id1_0_, user0_.username as username1_0_, user0_.password as password1_0_ from T_User user0_ where user0_.Id=?
Hibernate: select user0_.Id as Id1_0_, user0_.username as username1_0_, user0_.password as password1_0_ from T_User user0_ where user0_.Id=?
Hibernate: select user0_.Id as Id1_0_, user0_.username as username1_0_, user0_.password as password1_0_ from T_User user0_ where user0_.Id=?
Hibernate: select user0_.Id as Id1_0_, user0_.username as username1_0_, user0_.password as password1_0_ from T_User user0_ where user0_.Id=?

下面5条语句是怎么来的呢？

[阿_布]

Hibernate只不过给字段和表取了个别名啊！

[duanjianbo26]

Hibernate: select user0_.Id as Id1_0_, user0_.username as username1_0_, user0_.password as password1_0_ from T_User user0_ where user0_.Id=?
Hibernate: select user0_.Id as Id1_0_, user0_.username as username1_0_, user0_.password as password1_0_ from T_User user0_ where user0_.Id=?
Hibernate: select user0_.Id as Id1_0_, user0_.username as username1_0_, user0_.password as password1_0_ from T_User user0_ where user0_.Id=?
Hibernate: select user0_.Id as Id1_0_, user0_.username as username1_0_, user0_.password as password1_0_ from T_User user0_ where user0_.Id=?
Hibernate: select user0_.Id as Id1_0_, user0_.username as username1_0_, user0_.password as password1_0_ from T_User user0_ where user0_.Id=?


这几条语句是怎么来的？我想问的是

[duanjianbo26]

userfriend表的字段有

id userid userfriendid

映射关系

<many-to-one name="user" lazy="false">
<column name="userId" />
</many-to-one>
<many-to-one name="userFriend" lazy="false">
<column name="userIdFriend" />

[gzbtiantian]

T_UserFriend 和T_User是多对1关系，读取T_UserFriend的时候 把符合条件的T_UserFriend和T_UserFriend有关联的T_User都读取出来， 关键看你需要不，不要的话在 <many-to-one name="user" lazy="false" cascade="none" 就行了。

[wifewifewife]

建议lz断点一下就明白是什么原因了.

[duanjianbo26]

恩，还有个问题就是这里面关于user和 friend 的关联

其中有两个表，user和userfriend


user表中字段主要有 uid name...
userfriend 表 id userid userfriendid ，其中userid和userfriendid是user表的外键

，我的想法是user和friend是多对多的关系，中间表是userfriend.只不过friend和user实体是一个
但案例中却这样表示

有两个实体(pojo)
pubic class user{
}
public class userfriend
{
id;

user uid;
user fid;
}
userfriend配置文件
many-to-one name="user" lazy="false">
<column name="userId" />
</many-to-one>
<many-to-one name="userFriend" lazy="false">
<column name="userIdFriend" />

这样写的话 <many-to-one name="userFriend" lazy="false"> 这句该怎么解释呢？