Question

I have the following domain object:

public class Data {     public virtual int ID { get; set; }     public virtual DateTime TimeStamp { get; set; }     public virtual int Value { get; set; }      public virtual Channel Channel { get; set; }         }   

I’m using Repositories from Rhino.Commons. I need to select sum of values for few channels for some period. These values should be ordered by channel ID. I use the following query (in repository method):

var criteria = DetachedCriteria.For<LiveData>()             .Add(Restrictions.Le('TimeStamp', startDate))             .Add(Restrictions.Ge('TimeStamp', endDate))             .Add(Restrictions.InG<Channel>('Channel', channels))             .SetProjection(Projections.Sum('Value'))             .SetProjection(Projections.GroupProperty('Channel'));  long[] result = ReportAll<long>(criteria, Projections.ProjectionList(), Order.Asc('Channel')); 

And I receive error at the last line because this query returns not a list of long numbers. It returns a list of objects like this (it works with it):

public class ResultValue {     public virtual Channel Channel { get; set;}     public virtual int Value { get; set; }     public ResultValue()     {                 }      public ResultValue(int value, Channel channel)     {         this.Value = value;         this.Channel = channel;     } } 

This is because I’ve added Projections.GroupProperty(‘Channel’) projection to criteria to do a grouping. Is there any way to remove one of projections (Projections.GroupProperty(‘Channel’) from my sample) from resultset or to add a grouping without projection?

Answer 1

This is a pending NHibernate issue.