Question

我在程序员中发布了一个问题：https://softwareengineering.stackexchange.com/questions/315857/entity-framework-code-first-c-class-separation-and-eav

问题的一个解决方案是实体框架中的表拆分。到目前为止，我已经看过如何使用2个实体执行此操作，但不是3个或更多实体。

以下是我想与之共享相同表格的模型：

[Table("Tournament")]
    public partial class PGTournament : IImageable
    {

        public int Id { get; set; }
        public string Name { get; set; }
        public GameGenre GameGenre { get; set; }
        public TournamentFormat TournamentFormat { get; set; }

        public TournamentStatus Status { get; set; } 
        public string Description { get; set; }
        public virtual List<PrizePool> Prizes { get; set; }

        public DateTime StartDate { get; set; }
        public DateTime EndDate { get; set; }
        public virtual List<Participants.Participant> Participants { get; set; }
        public decimal Cost { get; set; }
        public string Streaming { get; set; }
        public int? ChallongeTournamentId { get; set; }
        public string Bracket { get; set; }
        public virtual List<TournamentMatch> Matches { get; set; }
        public int MainImageId { get; set; }
        public virtual Media MainImage { get; set; }
        public bool IsFollowUp { get; set; }
        public int? FollowUpTournamentId { get; set; }
        [ForeignKey("FollowUpTournamentId")]
        public virtual PGTournament FollowUptournament { get; set; }
        public int MediaID { get; set; }
        public int MainImageID { get; set; }

        //Properties that share same table:
        public virtual TournamentOrganizer Organizer { get; set; } //Change to Organizer
        public virtual TournamentOrganizerSetting OrganizerSetting { get; set; }
        public virtual TournamentSettings TournamentSettings { get; set; }
        public virtual TournamentRules Rules { get; set; }


    }

您看到的所有虚拟属性都没有List＆lt;＆gt;作为他们的类型，我希望他们共享一个相同的表（如果可能的话）。

[Table("Tournament")]
    public partial class TournamentOrganizer
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public string UserId { get; set; }
        [ForeignKey("UserId")]
        public AppUser User { get; set; }

        public int LogoId { get; set; }
        [ForeignKey("LogoId")]
        public Media Logo { get; set; }
        public virtual TournamentOrganizerSetting Settings { get; set; }
        public virtual TournamentRules Rules { get; set; }
        public virtual TournamentSettings TournamentSettings { get; set; }
        public virtual PGTournament Tournament { get; set; }


    }

[Table("Tournament")]
    public partial class TournamentSettings
    {
        public int Id { get; set; }
        public string Address { get; set; }
        public string LocationGoogleMaps { get; set; }
        public bool isOnline { get; set; }
        public int MaxPlayers { get; set; }
        public List<TournamentAssistant> TournamentAssistants { get; set; }

        public virtual TournamentOrganizer Organizer { get; set; } //Change to Organizer
        public virtual TournamentRules Rules { get; set; }
        public virtual TournamentOrganizerSetting OrganizerSettings { get; set; }
        public virtual PGTournament Tournament { get; set; }

    }

 [Table("Tournament")]
    public partial class TournamentOrganizerSetting
    {
        public int Id { get; set; }
        public string Location { get; set; }
        //Properties that share same table:
        public virtual TournamentOrganizer Organizer { get; set; } //Change to Organizer
        public virtual TournamentRules Rules { get; set; }
        public virtual TournamentSettings TournamentSettings { get; set; }
        public virtual PGTournament Tournament { get; set; }
    }

 [Table("Tournament")]
    public partial class TournamentRules
    {
        public int Id { get; set; }
        public string Bans { get; set; }
        public string Allowed { get; set; }
        public string Description { get; set; }
        public string FileName { get; set; }
        public string FilePath { get; set; }

        //Properties that share same table:
        public virtual TournamentOrganizer Organizer { get; set; } //Change to Organizer
        public virtual TournamentOrganizerSetting OrganizerSetting { get; set; }
        public virtual TournamentSettings TournamentSettings { get; set; }
        public virtual PGTournament Tournament { get; set; }
    }

我不知道为什么这些课程是偏袒的。我一直关注互联网上的几个教程，例如：http://www.c-sharpcorner.com/UploadFile/ff2f08/table-splitting-in-entity-framework-6-code-first-approach/

我无法让他们工作。

我甚至在DbModelBuilder中试过这个：

protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {    
            modelBuilder.Entity<PGTournament>().ToTable("Tournament");


            modelBuilder.Entity<PGTournament>()
                .HasKey(e => e.Id)
                .HasOptional(e => e.FollowUptournament)
                .WithMany();

            modelBuilder.Entity<PGTournament>()
                .HasKey(e => e.Id)
                .HasRequired(e => e.Organizer)
                .WithRequiredDependent(e => e.Organizer)

            modelBuilder.Entity<TournamentOrganizer>()
                .HasKey(e => e.Id)
                .HasRequired(e => e.Settings)
                .WithRequiredDependent(e => e.Organizer);

            modelBuilder.Entity<TournamentViewModel>()
                .HasKey(e => e.Id)
                .HasRequired(e => e.Settings)
                .WithRequiredDependent(e => e.Organizer);


            modelBuilder.Entity<TournamentOrganizer>().Map(m => m.ToTable("Tournament"));
            modelBuilder.Entity<TournamentOrganizerSetting>().Map(m => m.ToTable("Tournament"));

            base.OnModelCreating(modelBuilder);

        }

似乎没有StackOverflow帖子映射到3个或更多实体。

当我尝试运行它时，这是我得到的错误：

One or more validation errors were detected during model generation:

Pro_Gaming.Infrastructure.IdentityUserLogin: : EntityType 'IdentityUserLogin' has no key defined. Define the key for this EntityType.
Pro_Gaming.Infrastructure.IdentityUserRole: : EntityType 'IdentityUserRole' has no key defined. Define the key for this EntityType.
IdentityUserLogins: EntityType: EntitySet 'IdentityUserLogins' is based on type 'IdentityUserLogin' that has no keys defined.
IdentityUserRoles: EntityType: EntitySet 'IdentityUserRoles' is based on type 'IdentityUserRole' that has no keys defined.

Answer 1

这个答案来自ASP.NET论坛的Cole Wu： http://forums.asp.net/p/2093110/6043922.aspx?p=True&t=635968548324560382

答案如下：

 protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            //Do not delete this:
            base.OnModelCreating(modelBuilder);

            modelBuilder.Entity<Tournament>()
                .HasKey(e => e.TournamentId)
                .HasRequired(e => e.Rules)
                .WithRequiredPrincipal();

            modelBuilder.Entity<Tournament>()
                .HasKey(e => e.TournamentId)
                .HasRequired(e => e.TournamentSettings)
                .WithRequiredDependent();

            modelBuilder.Entity<TournamentOrganizer>()
                .HasKey(e => e.Id)
                .HasRequired(e => e.Settings)
                .WithRequiredDependent();


            modelBuilder.Entity<Tournament>().ToTable("Tournament");
            modelBuilder.Entity<TournamentRules>().ToTable("Tournament");
            modelBuilder.Entity<TournamentSettings>().ToTable("Tournament");

            modelBuilder.Entity<TournamentOrganizer>().ToTable("TournamentOrganizer");
            modelBuilder.Entity<TournamentOrganizerSetting>().ToTable("TournamentOrganizer");



        }

解释一下：

不需要部分课程（我说这是因为有一个表示您需要部分类的示例，但事实并非如此真）：
我还没有对此进行过测试，但我对所有要共享同一个表的类使用了相同的密钥。
modelBuilder.Entity＆lt; = TheEntity将是您希望所有内容映射到的主类。
如果您正在使用ASP.NET身份，并且您正在从IdentityDbContext扩展（这是我的情况），这非常重要在OnModelCreating方法中包含base.OnModelCreating（modelBuilder），否则你将被Identityissues命中，因为它没有找到IdenittyUser的主键。
1. 然后您将使用：

表拆分实体框架代码优先 - 3+实体

1 个答案: