Having a DTO like this:

public class CustomerDTO
{
     public int Id{get; set;}
     public int? Reference {get; set;}
}

How can I get it from

var q =_session.CreateSQLQuery("SELECT Id, Reference FROM customers")

If I use

q.SetResultTransformer(Transformers.AliasToBean<CustomerDTO>)

I get the following exception:

NHibernate.PropertyAccessException : The type System.Int32 can not be assigned to a property of type System.Nullable`1[System.Int32] setter of Customer.Reference

Try this:

var customers = _session.CreateSQLQuery("SELECT Id, Reference FROM customers")
    .AddScalar("Id", NHibernateUtil.Int32)
    .AddScalar("Reference", NHibernateUtil.Int32)
    .SetResultTransformer(Transformers.AliasToBean<CustomerDTO>())
    .List<CustomerDTO>();

Reference here.

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