nHibernate：無法解析屬性

Question

我花了數小時試圖弄清楚這一點，包括通過StackOverflow上所有以前提出的問題。

我試圖從EvaluationHeadId的TrainingCourse查詢，這就是工作得很好，不過，我設法得到它返回TrainingRoute「無法解析屬性：TrainingRoute.TrainingRouteDefinition的：Model.Entities.TrainingCourse」

它保存完美，我真正的問題是查詢。

更新爲：

  using (var session = SessionProvider.Instance.OpenSession()) 
      { 
       using (var transaction = session.BeginTransaction()) 
       { 
        dto = session.QueryOver<TrainingCourse>() 
          .JoinQueryOver<EvaluationHead>(p => p.EvaluationHeads) 
          .JoinQueryOver<TrainingRoute>(p => p.TrainingRoute) 
          .Where(c => c.EvaluationHeadID == headId) 
          .SelectList(l => l 
           .Select(h => h.TrainingCourseDefn).WithAlias(() => d.TrainingCourseDefn) 
           .Select(h => h.IsAvailable).WithAlias(() => d.IsAvailable) 
           .Select(h => h.TrainingRoute.TrainingRouteDefinition).WithAlias(() => d.TrainingRouteDefinition)) 
          .TransformUsing(Transformers.AliasToBean<TrainingCourseDTO>()) 
          .List<TrainingCourseDTO>(); 

        transaction.Commit();   
       } 
      } 

映射：

 public TrainingCourseMap() 
    { 
     Id(x => x.TrainingCourseID).GeneratedBy.Identity(); 
     Map(x => x.TrainingCourseDefn); 
     Map(x => x.IsAvailable); 
     Map(x => x.TrainingCourseCreatedBy); 
     Map(x => x.TrainingCourseDtCreation); 
     Map(x => x.TrainingCourseDtModified); 
     Map(x => x.TrainingCourseModifiedBy); 

     References(x => x.TrainingRoute).Column("TrainingRouteID").Cascade.None(); 
     HasManyToMany(x => x.EvaluationHeads).Table("EvaluationTraining").ParentKeyColumn("TrainingCourseID").ChildKeyColumn("EvaluationHeadID").Inverse().Cascade.All(); 
    } 

---

 public EvaluationHeadMap() 
    { 
     Id(x => x.EvaluationHeadID).GeneratedBy.Identity(); 
     Map(x => x.ManagerID); 
     Map(x => x.SupervisorID); 
     Map(x => x.EvaluationStartPeriod); 
     Map(x => x.EvaluationEndPeriod); 
     Map(x => x.EmployeeScalePoint); 
     Map(x => x.KRASignature); 
     Map(x => x.KRASignatureDate); 
     Map(x => x.DateCreated); 
     Map(x => x.DateModified); 
     HasMany(x => x.KeyResultAreas).KeyColumn("EvaluationHeadID").Cascade.All().Inverse(); 
     HasMany(x => x.Evaluations).KeyColumn("EvaluationHeadID").Inverse().Cascade.All(); 

     HasManyToMany(x => x.TrainingCourses).Table("EvaluationTraining").ParentKeyColumn("EvaluationHeadID").ChildKeyColumn("TrainingCourseID").Cascade.All().AsBag(); 

     References(x => x.Stage).Column("StageID").Cascade.None(); 
     References(x => x.Employee).Column("EmployeeID").Cascade.None(); 
     References(x => x.Employment).Column("EmploymentID").Cascade.None(); 
     //References(x => x.Manager).Column("EmployeeID"); 
     //References(x => x.Supervisor).Column("EmployeeID"); 
    } 

---

public TrainingRouteMap() 
    { 
     Id(x => x.TrainingRouteID).GeneratedBy.Identity(); 
     Map(x => x.TrainingRouteDefinition); 
     Map(x => x.TrainingRouteDescription); 
     HasMany(x => x.TrainingCourses).KeyColumn("TrainingRouteID").Cascade.AllDeleteOrphan().Inverse(); 
    } 

---

注意：我在TrainingCourse和TrainingRoute之間有另一個查詢，它根本沒有問題，甚至通過TrainingCourse.TrainingRoute.x模式訪問屬性。與這一個唯一的區別是，我也在查詢其他表。

Answer 1

TrainingRoute是TrainingCourse（以及EvaluationHeads）的參考性質。所以你也必須使用JoinQueryOver或JoinAlias。下面我們將創建用於別名的虛擬對象（全部設置爲空）。我們也拆分查詢的加入，因爲它們導致引用到新創建的查詢

TrainingCourse trainingCourse = null; 
TrainingRoute trainingRoute = null; 
EvaluationHead evaluationHead = null; 

var query = session.QueryOver<TrainingCourse>(() => trainingCourse); 

// here we can work with criteria against the TrainingRoute 
var referenceToTraingRouteQuery = query 
    .JoinQueryOver<TrainingRoute>(p => p.TrainingRoute,() => trainingRoute); 

// here we can filter the EvaluationHead collection 
var referenceToEvaluationHeadQuery = query // here we start again from the base query 
    .JoinQueryOver<EvaluationHead>(p => p.EvaluationHeads,() => evaluationHead) 
    .Where(c => c.EvaluationHeadID == headId); 

dto = query 
    .SelectList(l => l 
     .Select(() => trainingCourse.TrainingCourseDefn) 
        .WithAlias(() => d.TrainingCourseDefn) 
     .Select(() => trainingCourse.IsAvailable) 
        .WithAlias(() => d.IsAvailable) 

     // now let's used join alias 
     .Select(() => trainingRoute.TrainingRouteDefinition) 
        .WithAlias(() => d.TrainingRouteDefinition)) 

    .TransformUsing(Transformers.AliasToBean<TrainingCourseDTO>()) 
    .List<TrainingCourseDTO>(); 

或者你可以使用JoinAlias，多看看這裏16.4. Associations