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困惑了几天的问题 为什么hibernate执行了相同的SQL语句

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该帖已经被评为新手帖
作者 正文
   发表时间:2008-04-25  
 
package cn.phping.one2one_fk_2;

public class Passport_fk_2 {
	private int id;
	private String serial;
	private int expiry;
	private Person_fk_2 person_fk_2 ;  
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getSerial() {
		return serial;
	}
	public void setSerial(String serial) {
		this.serial = serial;
	}
	public int getExpiry() {
		return expiry;
	}
	public void setExpiry(int expiry) {
		this.expiry = expiry;
	}
	public Person_fk_2 getPerson_fk_2() {
		return person_fk_2;
	}
	public void setPerson_fk_2(Person_fk_2 person_fk_2) {
		this.person_fk_2 = person_fk_2;
	}

}
package cn.phping.one2one_fk_2;

public class Person_fk_2 {
	private int id;
	private String name;
	private Passport_fk_2 passport_fk_2;
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public Passport_fk_2 getPassport_fk_2() {
		return passport_fk_2;
	}
	public void setPassport_fk_2(Passport_fk_2 passport_fk_2) {
		this.passport_fk_2 = passport_fk_2;
	}
	



}


<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC 
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping >
<class name="cn.phping.one2one_fk_2.Passport_fk_2">
<id name="id">
  <generator class="native">
  </generator>
</id>
<property name="serial" />
<property name="expiry" />
<one-to-one name="person_fk_2" class="cn.phping.one2one_fk_2.Person_fk_2"
  property-ref="passport_fk_2"></one-to-one>
</class>
</hibernate-mapping>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC 
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
<class name="cn.phping.one2one_fk_2.Person_fk_2">
      <id name="id">
      <generator class="native"></generator>
 </id>
<property name="name" type="java.lang.String"/>
<many-to-one name="passport_fk_2"
  unique="true"></many-to-one>
</class>
</hibernate-mapping>

以上是两个POJO类,以及两个映射文件,两者关系是基于唯一外键的一对一关系,然后我写了测试类 用junit测试
package cn.phping.one2one_fk_2;
import java.util.Iterator;
import java.util.List;

import junit.framework.TestCase;

import org.hibernate.Session;

import cn.phping.junit.HibernateUtils;
public class Testone2one_fk_2 extends TestCase {
	Session session = null;
	@Override
	protected void setUp() throws Exception {
		session = HibernateUtils.currentSession();
	}

	@Override
	protected void tearDown() throws Exception {
	      HibernateUtils.closeSession();
	}

	public void  testSaveone2one_fk_2() {
		session.beginTransaction();
		Person_fk_2 person_fk_2 = new Person_fk_2();
		person_fk_2.setName("wuxuping");
		Passport_fk_2 passport_fk_2  = new Passport_fk_2();
		passport_fk_2.setSerial("2203222222222");
		passport_fk_2.setExpiry(25);
		passport_fk_2.setPerson_fk_2(person_fk_2);
		session.save(passport_fk_2);
		session.getTransaction().commit();
		}
	
	public void testGetDatas(){
		session.beginTransaction();
		List list = session.createQuery("from Passport_fk_2 p ").list();
	
		
	}
	
}

当我测试testGetDatas()方法时,测试的结果如下,当我数据库里有5条Passport_fk_2 hibernate执行了5条相同的语句,当我有100条时,也就有100条相同的sql 。不知道为什么,不知道小弟那里设置有错误
请高手们帮帮我,小弟不胜感激!!!!
Hibernate: select passport_f0_.id as id8_, passport_f0_.serial as serial8_, passport_f0_.expiry as expiry8_ from Passport_fk_2 passport_f0_
Hibernate: select person_fk_0_.id as id9_0_, person_fk_0_.name as name9_0_, person_fk_0_.passport_fk_2 as passport3_9_0_ from Person_fk_2 person_fk_0_ where person_fk_0_.passport_fk_2=?
Hibernate: select person_fk_0_.id as id9_0_, person_fk_0_.name as name9_0_, person_fk_0_.passport_fk_2 as passport3_9_0_ from Person_fk_2 person_fk_0_ where person_fk_0_.passport_fk_2=?
Hibernate: select person_fk_0_.id as id9_0_, person_fk_0_.name as name9_0_, person_fk_0_.passport_fk_2 as passport3_9_0_ from Person_fk_2 person_fk_0_ where person_fk_0_.passport_fk_2=?
Hibernate: select person_fk_0_.id as id9_0_, person_fk_0_.name as name9_0_, person_fk_0_.passport_fk_2 as passport3_9_0_ from Person_fk_2 person_fk_0_ where person_fk_0_.passport_fk_2=?
Hibernate: select person_fk_0_.id as id9_0_, person_fk_0_.name as name9_0_, person_fk_0_.passport_fk_2 as passport3_9_0_ from Person_fk_2 person_fk_0_ where person_fk_0_.passport_fk_2=?
   发表时间:2008-04-25  
你没看到执行SQL语句末尾的问号吗?那是参数占位符,它会被实际的参数值替代。参数不同取得的结果也就不同了
0 请登录后投票
   发表时间:2008-04-25  
可是我并没有添加参数啊 我只是想全部取出来
0 请登录后投票
   发表时间:2008-04-25  
你开启lazy fetch功能了吗?
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   发表时间:2008-04-25  
steven_652 写道
你开启lazy fetch功能了吗?

能说的具体点吗 可是别人的代码根本这样没问题啊
0 请登录后投票
   发表时间:2008-04-25  
两个实体之间的关联配置有错,你仔细检查一下吧
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