OKay, I am still struggling with the problem of persisting a parent and the child is not being persisted. I have read Chapter 8 of the docs dealing with Parent Child Relationships (like 4 times!), and in fact I am trying to execute the exact example illustrated in that chapter. I am not having much success, however.

Hibernate.cfg.xml
<hibernate-configuration>

<session-factory>
<property name="dialect">net.sf.hibernate.dialect.MySQLDialect</property>
<property name="hibernate.connection.driver_class">org.gjt.mm.mysql.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql://127.0.0.1/quickstart</property>
<property name="show_sql">true</property>


<!-- Mapping files -->
<mapping resource="Parent.hbm.xml"/>
<mapping resource="Child.hbm.xml"/>

</session-factory>

</hibernate-configuration>

Parent.hbm.xml
<hibernate-mapping>
<class name="Parent" table="parent">
<id name="id">
<generator class="identity"/>
</id>
<property name="name"/>
<set name="children" inverse="true" cascade="all">
<key column="parent_id"/>
<one-to-many class="Child"/>
</set>
</class>
</hibernate-mapping>

Child.hbm.xml
<hibernate-mapping>

<class name="Child" table="child">
<id name="id">
<generator class="identity"/>
</id>
<property name="name"/>
<many-to-one name="parent" column="parent_id" not-null="true"/>
</class>
</hibernate-mapping>

Test Code

Configuration cfg = new Configuration().configure("/hibernate.cfg.xml");
SessionFactory sf =cfg.buildSessionFactory();

Session sess = sf.openSession();
Parent p = (Parent) sess.load(Parent.class, new Integer(1));
Child c = new Child();
c.setName("Sam");
p.addChild(c);
sess.flush();
sess.close();

I do not get any exception, but nothing seems to happen. When I have the "show-sql" flag turned on, I see...

Hibernate: update child set name=?, parent_id=? where id=?

However, shouldn't it be an insert? I am thoroughly confused as to what is going on, so any help is greatly appreciated. I feel like I have followed the example in the docs exactly, but I obviously must be missing something. I have not provided the implementations of the Parent and Child classes, but can easily do so if needed. Thanks for any help!

Bryan

It doesn't look like you are saving anything in your main code loop. Just before you do session.flush() try adding:


Additionally you will need to specify cascade="all" or one of the other cascade options if you want the child persisted when you persist the parent. Otherwise you will have to add the above call for the child as well.

Above in Person.hmb.xml I have ....



Now according to the documentation from the Parent Child Relationships chapter....



I read this to mean that I should not need to explicitly call save() on either the parent or the child. Am I reading this documentation wrong? Perhaps I have the cascade in the wrong place? Thanks again for the help.

Bryan

add unsaved-value="0" to you mapping files for id column

>>I read this to mean that I should not need to explicitly call save() on >>either the parent or the child.

I think you need to call explict save on the parent object.

Correct me if i am wrong.