group by analog in Criteria

Question

I Use NHibernate criteria and it returns objects with same ids how I can create somethig like "group by" there?

    public List<ProducerRelation> GetByDateRangeAndUser(DateTime from, DateTime till, string user,
         ICollection exeptedIds)
    {
        var criteria = NHibernateSession.CreateCriteria(typeof(ProducerRelation));
        AddCriterionByRouteUnitDate(criteria, from, till, exeptedIds);
        criteria.Add(Restrictions.Eq(
                    String.Format("{0}.{1}", ProducerRelation.Properties.Order,
                        BackOffice.Core.Domains.Order.Properties.CreatedBy), user));
        return criteria.List<ProducerRelation>() as List<ProducerRelation>;
    }



    private void AddCriterionByRouteUnitDate(ICriteria crit, DateTime from, DateTime till,
        ICollection exeptedIds)
    {
        crit.CreateAlias(ProducerRelation.Properties.Order, ProducerRelation.Properties.Order);
        crit.CreateAlias(String.Format("{0}.{1}",
            ProducerRelation.Properties.Order,
            bModel.Order.Properties.RouteUnits), ProducerRelation.Properties.RouteUnit)
            .Add(Restrictions.Between(
                String.Format("{0}.{1}", ProducerRelation.Properties.RouteUnit, RouteUnit.Properties.DtStart),
                from, till))
            .Add(Restrictions.Not(
                Restrictions.In(ProducerRelation.Properties.Id, exeptedIds)
                ));
    }

Answer 1

Because your code is not reproduceable I'm just guessing that you might need to add a transformation at the end.

Try .SetResultTransformer(new DistinctRootEntityResultTransformer());