Joint query of Microsoft Dynamics CRM 4.0 entities

  ConditionExpression cond = new ConditionExpression();             cond.AttributeName = "new_nsrsbh";             cond.Values = new object[] { "21010277460473X" };             FilterExpression filter = new FilterExpression();             filter.Conditions = new ConditionExpression[] { cond };             filter.FilterOperator = LogicalOperator.And;                          LinkEntity link =new LinkEntity ();             link.LinkFromEntityName = EntityName.new_dj_kh_hykxx.ToString();             link.LinkFromAttributeName = "new_contactid";             link.LinkToEntityName = EntityName.account.ToString();             link.LinkToAttributeName = "primarycontactid";             link.LinkCriteria = filter;             QueryExpression query = new QueryExpression();             query.EntityName = EntityName.new_dj_kh_hykxx.ToString();             query.ColumnSet = new AllColumns();                                                query.LinkEntities = new LinkEntity[] { link };                         BusinessEntityCollection entity = service.RetrieveMultiple(query);             new_dj_kh_hykxx hyk = (new_dj_kh_hykxx) entity.BusinessEntities[0];