I've faced a problem using DB2
I have two tables: ParentTable and ChildTable
----ParentTable-----------------------------------------
<id name="Id" column="ID" type="Int32">
<generator class="native">
</generator>
</id>
<property name="Name" column="&quot;Name&quot;" type="String" length="255" />

<set name="Children" cascade="delete-orphan" lazy="false" inverse="true">
<key column="&quot;Parent_Id&quot;"/>
<one-to-many class="DataLayer.User, DataLayer"/>
</set>


----ChildTable-----------------------------------------
<id name="Id" column="ID" type="Int32">
<generator class="native">
</generator>
</id>
<property name="Name" column="&quot;Name&quot;" type="String" length="255" />
<many-to-one name="Parent" class="DataLayer.Parent, DataLayer" column="&quot;Parent_Id&quot;" />
------------------------------

When the "Child" table is empty everything is ok
otherwise I get an exception
[NHibernate.ADOException] {NHibernate.ADOException} NHibernate.ADOException
"could not initialize collection: [DataLayer.Parent.Children#1]"

Does anybody knows whats wrong

I would appreciate for a fast reply... this stuff is quite urgent for me and I still cannot find a solution
The fact is that this one-to-many construction was working perfectly with microsoft access. But when we migrated to DB2 v8.1.11.973 this problem occured.
I am not very experienced in NHibernate and I dot'n even know what is the reason of the failure :(



Maybe the information I gave was not full
so here is the database structure of my tables
-------------------------------------------------------------------------
--create table "Parent" (
"Name" VARCHAR(50) not null,
ID INTEGER not null
generated always as identity
);

ALTER TABLE "Parent" ADD CONSTRAINT ParentPK PRIMARY KEY ( ID) ;

create table "Child" (

"Name" VARCHAR(50) not null,
ID INTEGER not null
generated always as identity,
"Parent_Id" INTEGER not null
);

ALTER TABLE "Child" ADD CONSTRAINT ChildPK PRIMARY KEY ( ID) ;

alter table "Child"
add constraint "F_26_Ref" foreign key ("Parent_Id")
references "Node" (ID)
on delete cascade;

-----------------------------------------------------------------

Here is the full stack trace of my exception


at System.Data.Common.FieldNameLookup.GetOrdinal(String fieldName)
at System.Data.OleDb.OleDbDataReader.GetOrdinal(String name)
at NHibernate.Driver.NHybridDataReader.GetOrdinal(String name)
at NHibernate.Type.NullableType.NullSafeGet(IDataReader rs, String name)
at NHibernate.Type.NullableType.NullSafeGet(IDataReader rs, String[] names, ISessionImplementor session, Object owner)
at NHibernate.Collection.AbstractCollectionPersister.ReadKey(IDataReader dr, ISessionImplementor session)
at NHibernate.Loader.Loader.ReadCollectionElement(Object optionalOwner, Object optionalKey, IDataReader rs, ISessionImplementor session)
at NHibernate.Loader.Loader.GetRowFromResultSet(IDataReader resultSet, ISessionImplementor session, QueryParameters queryParameters, IList hydratedObjects, Object optionalObject, Object optionalId, Key[] keys, Boolean returnProxies)
at NHibernate.Loader.Loader.DoQuery(ISessionImplementor session, QueryParameters queryParameters, Object optionalObject, Object optionalId, Object[] optionalCollectionKeys, Boolean returnProxies)
at NHibernate.Loader.Loader.DoQueryAndInitializeNonLazyCollections(ISessionImplementor session, QueryParameters queryParameters, Object optionalObject, Object optionalId, Object[] optionalCollectionKeys, Boolean returnProxies)
at NHibernate.Loader.Loader.LoadCollection(ISessionImplementor session, Object[] ids, IType[] types)
at NHibernate.Loader.Loader.LoadCollection(ISessionImplementor session, Object id, IType type)
at NHibernate.Loader.OneToManyLoader.Initialize(Object id, ISessionImplementor session)
at NHibernate.Collection.AbstractCollectionPersister.Initialize(Object key, ISessionImplementor session)