hi everyone,
and sorry to bother you with another Parent/Children problem.

I'm just trying to do a simple session.save(parent) that should also save children. But it inserts the parent and then tries to update children (not saved yet)

Here is my code:

///////////////////////
[code]Session session = HibernateUtil.currentSession();
Transaction tx = session.beginTransaction();[/code]

Parent p = new Parent();
p.setName("parentName");
p.setChildren(new ArrayList());
Child c = new Child();
c.setName("childName");
c.setParent(p);
p.getChildren().add(c);
session.save(p);

tx.commit();
HibernateUtil.closeSession();
//////////////////////////

And here is the config:
<class name="xpetstore.domain.Parent" table="T_PARENT">
<id name="parentId" length="10">
<generator class="assigned"/>
</id>
<bag
name="children"
lazy="false"
inverse="true"
cascade="all"
>
<key column="parent_id" />
<one-to-many class="xpetstore.domain.Child"/>
</bag>
<property
name="name"
type="java.lang.String"
column="name"
length="20"
/>
</class>

<class name="xpetstore.domain.Child" table="T_CHILD"
dynamic-insert="true">
<id name="childId" length="10" >
<generator class="assigned"/>
</id>
<property
name="name"
type="java.lang.String"
column="name"
length="20"
/>
<many-to-one
name="parent"
class="xpetstore.domain.Parent"
column="parent_id"
not-null="true"
/>
</class>

At last (sorry if it's a little long) the error message:

Hibernate: insert into T_PARENT (name, parentId) values (?, ?)
Hibernate: update T_CHILD set name=?, parent_id=? where childId=?
12896 [http8080-Processor4] ERROR impl.SessionImpl - Could not synchronize database state with session
net.sf.hibernate.HibernateException: SQL update or deletion failed (row not found)
at net.sf.hibernate.impl.NonBatchingBatcher.addToBatch(NonBatchingBatcher.java:25)
at net.sf.hibernate.persister.EntityPersister.update(EntityPersister.java:672)
at net.sf.hibernate.persister.EntityPersister.update(EntityPersister.java:625)
at net.sf.hibernate.impl.ScheduledUpdate.execute(ScheduledUpdate.java:52)
at net.sf.hibernate.impl.SessionImpl.executeAll(SessionImpl.java:2308)
at net.sf.hibernate.impl.SessionImpl.execute(SessionImpl.java:2262)
at net.sf.hibernate.impl.SessionImpl.flush(SessionImpl.java:2187)
at net.sf.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:61)
at xpetstore.util.HibernateProductService.getProductAndItems(Unknown Source)
at xpetstore.web.struts.action.product.ProductAction.execute(Unknown Source)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:446)

I have read the documentation and the FAQs, but haven't found a solution.
I'm using MySql and an hibernate.cfg.xml file.

Thanks a lot for any help
Gilles

This one will help you http://www.hibernate.org/116.html#A11.
Read the doc on that subject too.

"assigned"...
now I understand what that means...
what an id**t...
You rock my world! Thanks a lot.

I've thus changed my id properties to be Long in my java code, and set the generator to "native". I'm using mysql.
It seems to be taking hilo as default algorithm (thus it needs an extra table...)

Is there anyway that the generator could use the auto_increment mysql feature alone (meaning incrementing ids as they are created?)

Thanks again.

I would be very surprised if MySql does not implement either sequence or idendity.

If I remember well, identity is supported.

try "identity" generator

Thanks Emanuel for your prompt answer even on Christmas eve:

when I use "increment", it works.
when I use "identity" it fails when creating the SessionFactory the first time:
java.lang.ExceptionInInitializerError
...
log from Tomcat:
Caused by: net.sf.hibernate.MappingException: Dialect does not support Caused by: net.sf.hibernate.MappingException: Dialect does not support identity key generation
at net.sf.hibernate.dialect.Dialect.getIdentitySelectString(Dialect.java:272)
at net.sf.hibernate.persister.AbstractEntityPersister.<init>(AbstractEntityPersister.java:639)
at net.sf.hibernate.persister.EntityPersister.<init>(EntityPersister.java:699)
at net.sf.hibernate.persister.PersisterFactory.createClassPersister(PersisterFactory.java:41)
at net.sf.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:137)
at net.sf.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:739)...

I have:
<property name="dialect">net.sf.hibernate.sql.MySQLDialect</property>

Any idea?
Thanks again
Gilles

So, I'm wrong on my guess on MySQL :-(

I guess I'll stay with increment since I'm not using a cluster.

Thanks a lot again for pointing me to the right direction,
"I owe you"

Thanks and like the good old saying:
"Meeeeeerry Christmas" (with santa voice:)

Thanks!
Gilles