虽然删除了父母，孩子被更新，而不是删除

Question

我的问题是，当我删除父子并没有被删除，而不是删除了孩子，孩子正在更新 这是输出

Hibernate: update employee_project set employeeNumber=null where employeeNumber=? 
Hibernate: delete from employee where EMPLOYEE_NUMBER=? 

时我删除父这是代码段的我跑

public boolean deleteEmployee(Employee employee) { 
     Transaction transaction = null; 
     boolean flag; 
     try { 
      transaction = session.beginTransaction(); 
      session.delete(employee); 
      session.flush(); 
      transaction.commit(); 
      flag = true; 
     } catch (HibernateException exception) { 
      if (transaction != null) 
       transaction.rollback(); 
      flag = false; 
     } 
     return flag; 
    } 

这是我父表Employee.hbm.xml

<hibernate-mapping package="com.nousinfo.tutorial.model"> 
    <class name="Employee" table="employee"> 
     <meta attribute="class-description"> 
      This class contains the employee detail 
     </meta> 
     <id name="employeeNumber" type="int" column="EMPLOYEE_NUMBER"> 

     </id> 
     <property name="firstName" type="string" column="FIRST_NAME"></property> 
     <property name="lastName" type="string" column="LAST_NAME"></property> 
    </property> 
     <set name="employeeProjects" cascade="all-delete-orphan"> 
      <key column="employeeNumber" /> 
      <one-to-many class="com.ravindrainfo.tutorial.model.EmployeeProject" /> 
     </set> 

    </class> 

</hibernate-mapping> 

，这是子表project.hbm.xml

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

<hibernate-mapping package="com.nousinfo.tutorial.model"> 
    <class name="EmployeeProject" table="employee_project"> 
     <meta attribute="class-description"> 
      This class contains the employee detail 
     </meta> 
     <composite-id> 
      <key-property name="employeeNumber" type="int" 
       column="EMPLOYEE_NUMBER"></key-property> 
      <key-property name="projectCode" type="string" column="PROJECT_CODE"></key-property> 
     </composite-id> 
     <property name="startDate" type="date" column="START_DATE"></property> 

     <many-to-one name="employee" class="com.ravindrainfo.tutorial.model.Employee"></many-to-one> 
    </class> 
</hibernate-mapping> 

这是我的员工POJO的

import java.io.Serializable; 
import java.util.Date; 

import java.util.Set; 

public class Employee implements Serializable { 

    private static final long serialVersionUID = 4314638638373270669L; 
    private int employeeNumber; 
    private String firstName; 
    private String lastName; 
     private Set<EmployeeProject> employeeProjects; 

    public String getFirstName() { 
     return firstName; 
    } 

    public void setFirstName(String firstName) { 
     this.firstName = firstName; 
    } 

    public String getLastName() { 
     return lastName; 
    } 

    public void setLastName(String lastName) { 
     this.lastName = lastName; 
    } 
     public Set<EmployeeProject> getEmployeeProjects() { 
     return employeeProjects; 
    } 

    public void setEmployeeProjects(Set<EmployeeProject> employeeProjects) { 
     this.employeeProjects = employeeProjects; 
    } 
     public int getEmployeeNumber() { 
     return employeeNumber; 
    } 

    public void setEmployeeNumber(int employeeNumber) { 
     this.employeeNumber = employeeNumber; 
    } 

} 

Answer 1

我不知道这个工程以XML为好，但要尽量修改

<set name="employeeProjects" cascade="all-delete-orphan"> 
     <key column="employeeNumber" /> 
     <one-to-many class="com.ravindrainfo.tutorial.model.EmployeeProject" /> 
</set> 

与

<set name="employeeProjects" cascade="all-delete-orphan" orphanRemoval="true"> 
     <key column="employeeNumber" /> 
     <one-to-many class="com.ravindrainfo.tutorial.model.EmployeeProject" /> 
</set> 

因此加入orphanRemoval="true"。

这适用于注释 @OneToMany(orphanRemoval=true)，所以我敢肯定它与XML工程，以及（实际上，你甚至可以删除 cascade="all-delete-orphan"相当安全）

编辑：我签出更多的信息，发现这页Hibernate Unidirectional Parent/Child relationship - delete() performs update on child table instead of delete，所以你可以尝试修改你的映射，加入inverse="true"而不是orphanRemoval。所以

<set name="employeeProjects" cascade="all-delete-orphan" inverse="true"> 
    <key column="employeeNumber" /> 
    <one-to-many class="com.ravindrainfo.tutorial.model.EmployeeProject" /> 
</set> 

Answer 2

我觉得级联应该是全部删除孤儿而不是全删除，孤儿

Hibernate文档中的摘录：

如果子对象的生命周期由父对象的生命周期限定，通过指定 cascade =“all，delete-orphan”（@ OneToMany（cascade = CascadeType.AL）将其设为生命周期对象L， orphanRemoval = true））。

裁判：http://docs.jboss.org/hibernate/core/3.6/reference/en-US/html/objectstate.html#objectstate-transitive