Question

我无法将我的应用程序插入到具有外键关系的表中。我正在使用SqLite3＆amp;单声道2.8。

我的sqlite脚本如下所示：

CREATE TABLE IF NOT EXISTS appointments (
   id INTEGER PRIMARY KEY AUTOINCREMENT,
   name VARCHAR(100) UNIQUE);

CREATE TABLE IF NOT EXISTS courses_appointments (
   course_code VARCHAR(50) NOT NULL REFERENCES courses (code),
   appointment_id INTEGER NOT NULL REFERENCES appointments (id));

CREATE TABLE IF NOT EXISTS courses (
   code VARCHAR(50) NOT NULL PRIMARY KEY,
   name VARCHAR(255) NOT NULL UNIQUE);

所以我有多对多的关系; 接下来，我有映射类：

[Table(Name="appointments")]
public partial class Appointment
{  
   private EntitySet<CourseAppointment> _courseAppointments;

   public Appointment()
   {
      _courseAppointments = new EntitySet<CourseAppointment>();
   }

   [Column(Name="id", AutoSync=AutoSync.OnInsert, IsPrimaryKey=true, IsDbGenerated=true)]
   public int Id { get; set; }

   [Column(Name="name", CanBeNull=false)]
   public string Name { get; set; }

   [Association(Storage="_courseAppointments", Name="appointments__courses_appointments", ThisKey="Id", OtherKey="AppointmentId")]

   public EntitySet<CourseAppointment> CourseAppointments
   {
      get { return _courseAppointments; }
      set { _courseAppointments.Assign(value); }
   }
}

[Table(Name="courses_appointments")]
public partial class CourseAppointment
{  
   private string _courseCode;
   private int _appointmentId;

   private EntityRef<Appointment> _appointment;
   private EntityRef<Course> _course;

   [Column(Name="_course_code", Storage="_courseCode", CanBeNull=false)]
   public string CourseCode
   {
      get
      {
         return _courseCode;
      }
      set
      {
         if (_course.HasLoadedOrAssignedValue)
            throw new ForeignKeyReferenceAlreadyHasValueException();

         this._courseCode = value;    
      } 
}

   [Column(Name="appointment_id", Storage="_appointmentId")]
   public int AppointmentId
   {
      get
      {
         return _appointmentId;
      }
      set
      {
         if (_appointment.HasLoadedOrAssignedValue)
            throw new ForeignKeyReferenceAlreadyHasValueException();

  _appointmentId = value;    
      }
   }

   [Association(Name="appointments__courses_appointments", Storage="_appointment", ThisKey="AppointmentId", OtherKey="Id", IsForeignKey=true, DeleteOnNull=true)]
   public Appointment Appointment
   {
      get
      {
         return _appointment.Entity;
      }
      set
      {
         var previousValue = _appointment.Entity;

  if (previousValue == value && _appointment.HasLoadedOrAssignedValue)
            return;

         if (previousValue != null)
         {
            _appointment.Entity = null;
     previousValue.CourseAppointments.Remove(this);
  }

         _appointment.Entity = value;

  if (value != null)
  {
     value.CourseAppointments.Add(this);
     _appointmentId = value.Id;
  }
         else
  {
     _appointmentId = 0;
  }    
      }
   }

   [Association(Name="courses__courses_appointments", Storage="_course", ThisKey="CourseCode", OtherKey="Code", IsForeignKey=true, DeleteOnNull=true)]
   public Course Course
   {
      get
      {
         return _course.Entity;
      }
      set
      {
         var previousValue = _course.Entity;

         if (previousValue == value && _course.HasLoadedOrAssignedValue)
     return;

  if (previousValue != null)
  {
            _course.Entity = null;
     previousValue.CourseAppointments.Remove(this);
  }

  _course.Entity = value;

  if (value != null)
         {
            value.CourseAppointments.Add(this);
     _courseCode = value.Code;
  }
         else
  {
     _courseCode = null;
  }    
      }
   }
}

[Table(Name="courses")]
public partial class Course
{    
   private EntitySet<CourseAppointment> _courseAppointments;

   public Course()
   {
      _courseAppointments = new EntitySet<CourseAppointment>();
   }

   [Column(Name="code", CanBeNull=false, IsPrimaryKey=true)]
   public string Code { get; set; }

   [Column(Name="name", CanBeNull=false)]
   public string Name { get; set; }

   [Association(Name="courses__courses_appointments", Storage="_courseAppointments", ThisKey="Code", OtherKey="CourseCode")]
   public EntitySet<CourseAppointment> CourseAppointments
   {
      get { return _courseAppointments; }
      set { _courseAppointments.Assign(value); }
   }
}
}

当我执行代码时：

var a =new Appointment() { Name = "abracadabra" };
appointments.InsertAllOnSubmit(entities);
dc.SubmitChanges();

抛出异常：

System.ArgumentException: Value does not fall within the expected range. at DbLinq.Util.MemberInfoExtensions.GetMemberValue (System.Reflection.MemberInfo memberInfo, System.Object o) [0x00000] in :0 at System.Data.Linq.DataContext+c__AnonStorey2C.<>m__29 (System.Data.Linq.Mapping.MetaDataMember m) [0x00000] in :0 at System.Linq.Enumerable+c__Iterator10`2[System.Data.Linq.Mapping.MetaDataMember,System.Object].MoveNext () [0x00000] in :0 at System.Collections.Generic.List`1[System.Object].AddEnumerable (IEnumerable`1 enumerable) [0x00000] in :0 at System.Collections.Generic.List`1[System.Object]..ctor (IEnumerable`1 collection) [0x00000] in :0 at System.Linq.Enumerable.ToList[Object] (IEnumerable`1 source) [0x00000] in :0 at System.Data.Linq.DataContext.UpdateReferencedObjects (System.Object root) [0x00000] in :0 at System.Data.Linq.DataContext.InsertEntity (System.Object entity, DbLinq.Data.Linq.Sugar.QueryContext queryContext) [0x00000] in :0 at System.Data.Linq.DataContext.SubmitChangesImpl (ConflictMode failureMode) [0x00000] in :0 at System.Data.Linq.DataContext.SubmitChanges (ConflictMode failureMode) [0x00000] in :0 at System.Data.Linq.DataContext.SubmitChanges () [0x00000] in :0 at Controllers.HomeController.InsertAppointments (System.Data.Linq.DataContext dc) [0x00000] in :0 at Controllers.HomeController.Index () [0x00000] in :0

DataContext.Log包含：

INSERT INTO "appointments" ("name") VALUES (:Name) -- :Name: Input String (Size = 0; Prec = 0; Scale = 0) [слесарь по обслуживанию буровых 4-5 разряда] -- Context: SQLite Model: AttributedMetaModel Build: 3.5.0.0 SELECT last_insert_rowid() -- Context: SQLite Model: AttributedMetaModel Build: 3.5.0.0

当我在Appointment.CourseAppointments上评论AssociationAttribute时，一切正常......

Answer 1

是的，确实如此！我必须将CourseAppointment.CourseCode和CourseAppointment.AppointmentId标记为分布式主键

IsPrimaryKey =真

Mono是否支持正确处理System.Data.Linq.Mapping.AssociationAttribute

1 个答案: