public void UploadPersons(List<Persona> persons)
        {
            try
            {
                var factory = GetFactory();

                using (var session = factory.OpenSession())
                {
                    using (var transaction = session.BeginTransaction())
                    {
                        foreach (var person in persons)
                        {
                            var oldPerson = session.Query<Persona>().SingleOrDefault(p => p.ID == person.ID);
                           
                            if (oldPerson != null)
                            {
                                person.PKId = oldPerson.PKId;

                                foreach (var relative in oldPerson.Relatives)
                                {
                                    session.Delete(relative);
                                }

                                session.Merge(person);
                            }
                            else
                            {
                                session.Save(person);
                            }

                            
                        }

                        transaction.Commit();
                    }
                }
            }
            catch (Exception ex)
            {
                var logWriter = EnterpriseLibraryContainer.Current.GetInstance<LogWriter>();
                logWriter.Write(ex);

                throw ex;
            }
        }

[DataContract]
    public class Relative
    {
        public virtual int Id { get; set; }

        [DataMember]
        public virtual Persona Persona { get; set; }
    }

   [DataContract(IsReference=true)]
    public class Persona
    {
        public Persona()
        {
            this.Relatives = new List<Relative>();
        }

        [DataMember]
        public virtual IList<Relative> Relatives
        {
            get;
            set;
        }


        public virtual int PKId { get; set; }
        
        [DataMember]
        public virtual Guid ID
        {
            get;
            set;
        }
     }

public class PersonaMapping : ClassMap<Persona>
    {
        public PersonaMapping()
        {
            this.Table("PERSONA");

            this.Id(p => p.PKId, "ID").GeneratedBy.TriggerIdentity();

            this.Map(p => p.ID, "ARM_ID");
           

            this.HasMany(x => x.Relatives)
                .KeyColumn("PERS_ID")
                .Fetch.Join()
                .Inverse()                
                .Cascade.All();
        }

public class RelativeMapping : ClassMap<Relative>
    {
        public RelativeMapping()
        {
            this.Table("FAM_MEMBERS");

            this.Id(r => r.Id).GeneratedBy.TriggerIdentity();

            this.References(r => r.Persona)
                .Column("PERS_ID")
                .Cascade.All();
        }
    }

person.PKId = oldPerson.PKId;

foreach (var relative in oldPerson.Relatives)
{
     session.Delete(relative);
}

public class RelativeMapping : ClassMap<Relative>
    {
        public RelativeMapping()
        {
            this.Table("FAM_MEMBERS");

            this.Id(r => r.Id).GeneratedBy.TriggerIdentity();

            this.References(r => r.Persona)
                .Column("PERS_ID")
                .Cascade.All();
        }
    }