NHibernate returning duplicate object in child collections when using Fetch
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                UpTheCreek
            
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        Published on 2011-01-17T14:32:50Z
        Indexed on 
            2011/01/18
            1:53 UTC
        
        
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nhibernate
When doing a query like this (using Nhibernate 2.1.2):
 ICriteria criteria = session.CreateCriteria<MyRootType>()
                .SetFetchMode("ChildCollection1", FetchMode.Eager)
                .SetFetchMode("ChildCollection2", FetchMode.Eager)
                .Add(Restrictions.IdEq(id));
I am getting multiple duplicate objects in some cartesian fashion.  E.g. if ChildCollection1 has 3 elements, and ChildColection2 has 2 elements then I get results with each element in ChildColection1 one duplicated, and each element in ChildColection2 triplicated!  This was a bit of a WTF moment for me...
So how to do this correctly?
- Is using SetFetchMode like this only supported when specifying one collection?
- Am I just using it wrong (I've seen some references to results transformers, but imagined this would be simplier).
- Is this something that's different in NH3?
Update:
As per Felice's suggestion, I tried using the DistinctRootEntity transformer, but this is still returning duplicates. Code:
ICriteria criteria = session.CreateCriteria<MyRootType>()
                .SetFetchMode("ChildCollection1", FetchMode.Eager)
                .SetFetchMode("ChildCollection2", FetchMode.Eager)
                .Add(Restrictions.IdEq(id));
 criteria.SetResultTransformer(Transformers.DistinctRootEntity);
 return criteria.UniqueResult<MyRootType>();
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