Using cascading update()

ramchandar_k · **Posted:** Fri Oct 31, 2003 4:03 am

Hi,

I have Department-has-Employee(s) relationship. I want to update the department like this

- update Employee record if the id in transient object is set
- insert a new Employee record for Department if id is not set
- delete all Employee records that are in the database but not in the getEmployees() collection of Department.

The first 2 cases work as mentioned in 8.4. There is not mention of delete of child records in 8.4. Can the third case be made to work with Hibernate? If yes, what do I need to do?

Thank you.

Ram.[/b]

emmanuel · **Posted:** Fri Oct 31, 2003 4:23 am

If you want that any orphan employee be deleted, use the cascade=""all-delete-ophan"

ramchandar_k · **Posted:** Fri Oct 31, 2003 5:12 am

Hi,

I turned on cascade="all-delete-orphan" and it now throws an exception

Quote:

You may not dereference a collection with cascade="all-delete-orphan"

I have not changed anything else except the cascade for Department

Code:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN" "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">

<hibernate-mapping>
   <class name="com.infosys.j2ee.cmptest.model.Department" table="DepartmentEJBTable">
   <id name="primaryKey">
      <generator class="sequence">
         <param name="sequence">test2_seq</param>
      </generator>
   </id>
   <property name="name">
      <column name="NAME"/>
   </property>
   <property name="location">
      <column name="LOCATION"/>
   </property>
   <bag name="employees" inverse="true" outer-join="true" cascade="all-delete-orphan">
      <key column="departmentid"/>
      <one-to-many class="com.infosys.j2ee.cmptest.model.Employee"/>
   </bag>
   
   </class>

   <class name="com.infosys.j2ee.cmptest.model.Employee" table="EmployeeEJBTable">
   <id name="primaryKey">
      <generator class="sequence">
         <param name="sequence">test2_seq</param>
      </generator>
   </id>
   <property name="name">
      <column name="NAME"/>
   </property>
   <property name="employeeNumber">
      <column name="EMPLOYEENUMBER"/>
   </property>
   <property name="hireDate">
      <column name="HIREDATE"/>
   </property>
   <property name="salary">
      <column name="SALARY"/>
   </property>   
   <many-to-one name="department" class="com.infosys.j2ee.cmptest.model.Department" column="departmentid" cascade="all"/>
   </class>      
</hibernate-mapping>

emmanuel · **Posted:** Fri Oct 31, 2003 5:28 am

http://forum.hibernate.org/old/918689.html

When using all-delete-orphan, you're supposed to keep the actual hibernate wrapper collection, to let hibernate know which objects are really orphans