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我有一个包含多个字段的表，这些字段是另一个表中主键的外键。例如 ：

Fixture Id (PK)
HomeTeamId (FK to Team.TeamId)
AwayTeamId (FK to Team.TeamId)
HomeTeamCoachId (FK to Coach.CoachId)
AwayTeamCoachId (FK to Coach.CoachId)

使用 FixtureId 的外键将此数据分成 2 个表 HomeTeam 和 AwayTeam 会更好吗？这是当前由 Entity Framework 生成的：

FixtureId PK
HomeTeamId int
AwayTeamId int
HomeTeamCoachId int
AwayTeamCoachId int
AwayTeam_TeamId FK
HomeTeam_TeamId FK
AwayTeamCoach_CoachId FK
HomeTeamCoach_CoachId FK

这是通过此类生成的：

public partial class Fixture
{
    public int FixtureId { get; set; }

    //foreign key
    public int AwayTeamId { get; set; }
    //navigation properties
    public virtual Team AwayTeam { get; set; }

    //foreign key
    public int HomeTeamId { get; set; }
    //navigation properties
    public virtual Team HomeTeam { get; set; }

    //foreign key
    public int AwayCoachId { get; set; }
    //navigation properties
    public virtual Coach AwayCoach { get; set; }

    //foreign key
    public int HomeCoachId { get; set; }
    //navigation properties
    public virtual Coach HomeCoach { get; set; }
}

谁能告诉我这是否是正确的方法？

编辑：回复 Slauma

所以我的课基本上是这样的？或者 OnModelCreating 中的配置是否意味着我的 Fixture 类中不需要一些与外键相关的代码？

 protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        // Entity Type Configuration
        modelBuilder.Configurations.Add(new TeamConfiguration());
        modelBuilder.Configurations.Add(new CoachConfiguration());
        modelBuilder.Configurations.Add(new FixtureConfiguration());

        modelBuilder.Entity<Fixture>()
            .HasRequired(f => f.AwayTeam)
            .WithMany()
            .HasForeignKey(f => f.AwayTeamId)
            .WillCascadeOnDelete(false);

        modelBuilder.Entity<Fixture>()
            .HasRequired(f => f.HomeTeam)
            .WithMany()
            .HasForeignKey(f => f.HomeTeamId)
            .WillCascadeOnDelete(false);

        modelBuilder.Entity<Fixture>()
            .HasRequired(f => f.AwayCoach)
            .WithMany()
            .HasForeignKey(f => f.AwayCoachId)
            .WillCascadeOnDelete(false);

        modelBuilder.Entity<Fixture>()
            .HasRequired(f => f.HomeCoach)
            .WithMany()
            .HasForeignKey(f => f.HomeCoachId)
            .WillCascadeOnDelete(false);
    }

public partial class Fixture
{
    public int FixtureId { get; set; }
    public string Season { get; set; }
    public byte Week { get; set; }

    //foreign key
    public int AwayTeamId { get; set; }
    //navigation properties
    public virtual Team AwayTeam { get; set; }

    //foreign key
    public int HomeTeamId { get; set; }
    //navigation properties
    public virtual Team HomeTeam { get; set; }

    //foreign key
    public int AwayCoachId { get; set; }
    //navigation properties
    public virtual Coach AwayCoach { get; set; }

    //foreign key
    public int HomeCoachId { get; set; }
    //navigation properties
    public virtual Coach HomeCoach { get; set; }

    public byte AwayTeamScore { get; set; }
    public byte HomeTeamScore { get; set; }
}
4

2 回答 2

10

显然 EF 没有检测到您的int属性，例如AwayTeamId导航属性的外键，AwayTeam因为其中的主键属性Teamis not Idbut TeamId。AwayTeamTeamId如果 FK 被命名为 like或者主键属性Team是否具有 name ，它可能会检测到 FK Id。

如果您不想根据 EF 约定更改这些属性名称，您可以使用数据注释定义 FK：

[ForeignKey("AwayTeam")]
public int AwayTeamId { get; set; }
public virtual Team AwayTeam { get; set; }

// the same for the other three FKs

或流利的 API：

modelBuilder.Entity<Fixture>()
    .HasRequired(f => f.AwayTeam)
    .WithMany()
    .HasForeignKey(f => f.AwayTeamId)
    .WillCascadeOnDelete(false);

// the same for the other three FKs

我已禁用级联删除，因为默认情况下它将为所需的关系启用。但是因为您与Team表（以及Coach表）有两个必需的关系，这将导致两个级联删除路径从FixturetoTeam和Coach. FixtureSQL Server 中禁止使用多个级联删除路径，因此您必须对andTeam之间（以及 and 之间Fixture）的两种关系中的至少一种禁用级联删除Coach。

于 2012-11-11T14:45:59.970 回答
1

我尝试过这种方式并工作

主键表

public class TravelCity
{
    [Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int CityId { get; set; }
    public string CityName { get; set; }
    public string CityDesc { get; set; }
    public string Status { get; set; }
}

具有外键的表

  public class TravelDetails
    {
    [Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public Int64 TravelId { get; set; }

    public Int32 FromLocation { get; set; }
    [ForeignKey("FromLocation"),InverseProperty("CityId")]
    public virtual TravelCity TravelCityFrom { get; set; }

    public Int32 ToLocation { get; set; }
    [ForeignKey("ToLocation"), InverseProperty("CityId")]
    public virtual TravelCity TravelCityTo { get; set; }


    public Int32 CurrentCity { get; set; }
    [ForeignKey("ToLocation"), InverseProperty("CityId")]
    public virtual TravelCity TravelCityCurrent{ get; set; }

}

试试这种方式，它会很好地工作..干杯:)

于 2013-10-18T05:07:46.000 回答