Hibernate version:
1.0.2.0
Mapping documents:
Parent.hbm.xml
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.0">
<class name="HYLQ.Core.Domain.Parent, HYLQ.Core" table="Parent">
<id name="Id" column="Id">
<generator class="assigned" />
</id>
<property name="Title" type="String" length="200" />
<bag name="Childs" lazy="true" inverse="true" cascade= "all-delete-orphan">
<key column="pid" />
<one-to-many class="HYLQ.Core.Domain.Child, HYLQ.Core" />
</bag>
</class>
</hibernate-mapping>

Child.hbm.xml
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.0">
<class name="HYLQ.Core.Domain.Child, HYLQ.Core" table="Child">
<id name="Id" column="Id">
<generator class="assigned" />
</id>
<property name="Memo" type="String" length="200" />
<many-to-one name="parent" class="HYLQ.Core.Domain.Parent, HYLQ.Core" column="pid" />
</class>
</hibernate-mapping>



Code between sessionFactory.openSession() and session.close():
using (ISession session = TestCategory.Factory.OpenSession())
{
int id = 1;

Parent parent = new Parent();

parent.Id = id;
parent.Title = "tetetet";

Child child = new Child();
child.Id = 1;
child.Memo = "222";
child.parent = parent;

parent.Childs.Add(child);

ITransaction trans = session.BeginTransaction();

try
{
session.Save(parent);
trans.Commit();
}
catch
{
trans.Rollback();
throw;
}
}



Full stack trace of any exception that occurs:

Test method TestProject1.TestCategory.AddParentChild threw exception: NHibernate.HibernateException: SQL insert, update or delete failed (expected affected row count: 1, actual affected row count: 0). Possible causes: the row was modified or deleted by another user, or a trigger is reporting misleading row count..

Name and version of the database you are using:
MS Sql 2000

create table Parent
(
Id int not null,
Title varchar(200) null,
primary key(Id)
)
go

create table Child
(
Id int not null,
pid int not null,
memo varchar(200) null,
primary key(Id)

)
go

Can you enable SQL logging? I'm curious to see if an update or insert is being created.

Simply set show_sql=true in your config file.

If you're using the NHibernate config handler then add this:


If you're using the name-value handler then add this:


Then, make sure you have log4net set up to capture something... put this in your config if you don't have it already:


That'll give you the SQL interleaved with the error.... immensely helpful for debugging.