Apparenlty this is a limitation in the recursive load cycle of the stateless session whereby the temporary persistence context was being cleared on each recursive load, meaning previously loaded entities were not in the entity map.
This issue was fixed in Hibernate, and I've ported the fix over to NHibernate here: http://216.121.112.228/browse/NH-2669 -r On Thu, Apr 21, 2011 at 5:35 PM, Rory Plaire <[email protected]> wrote: > Hi all - > > I'm cross-posting this from SO, since although this is the "official" > channel, there is better findability over there. > > > http://stackoverflow.com/questions/5751197/eager-fetching-of-a-great-grandchild-collection-using-a-stateless-session-via-nhi > > I'm using an NHibernate Stateless Session to load bulk data into the > database. As data is loaded, later entities need to lookup previous entities > in order to add them to child collections. This operation involves needing > data on a grandchild object, which in turn needs a great-grandchild > collection to be available. > > The criteria looks like this: > > var result = InternalRepository.CreateCritera<Root>() > > .SetResultTransformer(Transformers.DistinctRootEntity) > > .Add(Restrictions.IdEq(id)) > > .SetFetchMode("Child", FetchMode.Eager) > > .CreateAlias("Child", "a", JoinType.LeftOuterJoin) > > .SetFetchMode("a.Grandchild", FetchMode.Eager) > > .CreateAlias("Grandchild", "b", JoinType.LeftOuterJoin) > > .SetFetchMode("b.GreatGrandchildCollection", FetchMode.Eager) > > .UniqueResult<Root>(); > > When I execute this, TwoPhaseLoad throws an exception during > InitializeEntity since the session's persistence context entity entries > are empty: > > at NHibernate.Engine.TwoPhaseLoad.InitializeEntity(Object entity, Boolean > readOnly, ISessionImplementor session, PreLoadEvent preLoadEvent, > PostLoadEvent postLoadEvent) in TwoPhaseLoad.cs: line 64 > > at NHibernate.Loader.Loader.InitializeEntitiesAndCollections(IList > hydratedObjects, Object resultSetId, ISessionImplementor session, Boolean > readOnly) in Loader.cs: line 603 > > at NHibernate.Loader.Loader.DoQuery(ISessionImplementor session, > QueryParameters queryParameters, Boolean returnProxies) in Loader.cs: line 472 > > at > NHibernate.Loader.Loader.DoQueryAndInitializeNonLazyCollections(ISessionImplementor > session, QueryParameters queryParameters, Boolean returnProxies) in > Loader.cs: line 243 > > at NHibernate.Loader.Loader.DoList(ISessionImplementor session, > QueryParameters queryParameters) in Loader.cs: line 1694 > ... > > The entity the loader is looking up is the Child entity. Why is the > persistence context entries map empty here? The object is apparently being > fetched (the correct SQL is generated and returns correct results), and the > "Child" entity is created correctly. Why is the entity construction state > incorrect? Does it have to do with how the stateless session uses the > temporary persistence context during eager loads? > -- You received this message because you are subscribed to the Google Groups "nhusers" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/nhusers?hl=en.
