hibernate3,many-to-one join 查询结果怎么会返回两个对象？

应用场景：
我有一张订单表，一张代理商表，我订单表和代理商设置为many-to-one。

public class ProxyCustomer {
    private int id;
}

 public class Order {
     private int id;
     private ProxyCustomer proxyCustomer;
 }

many-to-one 配置如下：

<many-to-one name="proxyCustomer" column="proxy_customer_id" class="com.pro.entity.ProxyCustomer" not-null="false" fetch="join" lazy="false"/>

执行查询后，为什么list中会返回两个对象，一个是Order对象，一个是ProxyCustomer对象
而我期望只要一个Order对象，因为Order对象里包含了ProxyCustomer对象。
debug 看到的现象如下截图：

http://zhidao.baidu.com/link?url=HbJiHNgaEqFJHnPbVgqZFXJ76fPoS8hLM_8Vpwx6rfZtMKOFKtUsPZrxP0kcAihuLqRC8n1jOdIxc4QpkS9yorj3huDRFgS3g1rT4uKeHHe

我的写法打印出来的sql已经是left join了：

 SELECT this_.id                      AS id21_1_,
  this_.order_id                     AS order2_21_1_,
  this_.pipeline_order_id            AS pipeline3_21_1_,
  this_.reference_id                 AS reference4_21_1_,
  this_.username                     AS username21_1_,
  this_.phone                        AS phone21_1_,
  this_.status                       AS status21_1_,
  this_.type                         AS type21_1_,
  this_.return_code                  AS return9_21_1_,
  this_.return_message               AS return10_21_1_,
  this_.return_date                  AS return11_21_1_,
  this_.final_price                  AS final12_21_1_,
  this_.creation_date                AS creation13_21_1_,
  this_.created_by                   AS created14_21_1_,
  this_.updated_date                 AS updated15_21_1_,
  this_.updated_by                   AS updated16_21_1_,
  this_.box_id                       AS box17_21_1_,
  this_.proxy_customer_id            AS proxy18_21_1_,
  proxycusto2_.id                    AS id28_0_,
  proxycusto2_.updated_date          AS updated2_28_0_,
  proxycusto2_.username              AS username28_0_,
  proxycusto2_.password              AS password28_0_,
  proxycusto2_.name                  AS name28_0_,
  proxycusto2_.company               AS company28_0_,
  proxycusto2_.contact_person        AS contact7_28_0_,
  proxycusto2_.contact_phone         AS contact8_28_0_,
  proxycusto2_.address               AS address28_0_,
  proxycusto2_.balance               AS balance28_0_,
  proxycusto2_.security_deposit      AS security11_28_0_,
  proxycusto2_.warn_balance          AS warn12_28_0_,
  proxycusto2_.parent_proxy_customer AS parent13_28_0_,
  proxycusto2_.api_status            AS api14_28_0_,
  proxycusto2_.status                AS status28_0_,
  proxycusto2_.sms_notify            AS sms16_28_0_,
  proxycusto2_.email_notify          AS email17_28_0_,
  proxycusto2_.email_notify_list     AS email18_28_0_,
  proxycusto2_.phone_notify_list     AS phone19_28_0_,
  proxycusto2_.creation_date         AS creation20_28_0_,
  proxycusto2_.created_by            AS created21_28_0_,
  proxycusto2_.updated_by            AS updated22_28_0_
FROM pro_order this_
LEFT OUTER JOIN pro_proxy_customer proxycusto2_
ON this_.proxy_customer_id=proxycusto2_.id;

看你的sql就很明白啊，因为你的代理商表有2条满足这个订单，sql肯定返回2条查询结果，这很正常。
正常的hibernate得关联查询应该是有2个sql而不是合并成一个sql查询。

LEFT OUTER JOIN 一个表满足条件的行，和另一个表的所有行
左外连接 包含左边表的全部行（不管右边的表中是否存在与它们匹配的行），以及右边表中全部匹配的行