在实体框架6中，仅将现有的db映射到现有的poco，而不需要设计器或CodeFirst

关于在CodePlex上关闭这个工作项的注释声称自EF 6以来在TPT映射中定义父实体和子实体的不同键列名称使用Code-First工作。如果这是真的，下面的Code-First映射应该允许映射你的模型和数据库:

modelBuilder.Entity<Record>()
    .ToTable("YourRecordTableName");
modelBuilder.Entity<Record>()
    .HasKey(r => r.Ndx);
modelBuilder.Entity<Record>()
    .Property(r => r.Ndx)
    .HasColumnName("ndx"); // probably redundant because case doesn't matter
modelBuilder.Entity<Record>()
    .Property(r => r.CreatedAt)
    .HasColumnName("created");
modelBuilder.Entity<Patient>()
    .ToTable("YourPatientTableName");
modelBuilder.Entity<Patient>()
    .Property(r => r.Ndx)   // Yes, no typo: It must be Ndx, NOT RecordNdx !
    .HasColumnName("record_ndx");
modelBuilder.Entity<Patient>()
    .Ignore(r => r.RecordNdx);

最后一个映射(忽略RecordNdx属性)很重要。这意味着您的键属性将是Patient.Ndx。我不认为你可以在派生类中设置任何属性为键属性。key属性必须始终位于继承层次结构的基类中。然而，这个属性可以映射两次(或者通常在TPT继承链中每个实体一次)到每个表的不同列名——从EF 6开始。

完全去掉RecordNdx属性将是最干净的解决方案。但是既然你说你不能触摸你的属性，那么至少将RecordNdx的值与Ndx属性耦合是有意义的(如果你可以改变属性的getter和setter):

public virtual int RecordNdx
{
    get { return Ndx; }
    set { Ndx = value; }
}

编辑

我刚刚用EF 6.1测试了上面的Code-First映射，它确实有效!Record表中的主键列为ndx, Patient表中的主键列为record_ndx。在这些EF之间创建了TPT映射所需的一对一关系。

编辑2

这是我使用的完整的测试程序(当前的EF 6.1 Nuget包，.NET 4.5, VS 2012, SQL Server 2012 Express):

using System;
using System.Data.Entity;
namespace EFTPT6
{
    public class Record
    {
        public virtual int Ndx { get; set; }
        public virtual DateTime CreatedAt { get; set; }
    }
    public class Patient : Record
    {
        public virtual int RecordNdx { get; set; }
        public virtual string Name { get; set; }
    }
    public class MyContext : DbContext
    {
        public DbSet<Record> Records { get; set; }
        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Entity<Record>()
                .ToTable("Records");
            modelBuilder.Entity<Record>()
                .HasKey(r => r.Ndx);
            modelBuilder.Entity<Record>()
                .Property(r => r.Ndx)
                .HasColumnName("ndx");
            modelBuilder.Entity<Record>()
                .Property(r => r.CreatedAt)
                .HasColumnName("created");
            modelBuilder.Entity<Patient>()
                .ToTable("Patients");
            modelBuilder.Entity<Patient>()
                .Property(r => r.Ndx)
                .HasColumnName("record_ndx");
            modelBuilder.Entity<Patient>()
                .Ignore(p => p.RecordNdx);
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            Database.SetInitializer(new DropCreateDatabaseAlways<MyContext>());
            using (var ctx = new MyContext())
            {
                ctx.Database.Initialize(true);
                string sql = ctx.Records.ToString();
            }
        }
    }
}

程序末尾的字符串sql是:

SELECT 
    CASE WHEN ( NOT (([Project1].[C1] = 1) AND ([Project1].[C1] IS NOT NULL)))
        THEN '0X'
        ELSE '0X0X'
    END AS [C1], 
    [Extent1].[ndx] AS [ndx], 
    [Extent1].[created] AS [created], 
    CASE WHEN ( NOT (([Project1].[C1] = 1) AND ([Project1].[C1] IS NOT NULL)))
        THEN CAST(NULL AS varchar(1))
        ELSE [Project1].[Name]
    END AS [C2]
    FROM  [dbo].[Records] AS [Extent1]
    LEFT OUTER JOIN  (SELECT 
        [Extent2].[record_ndx] AS [record_ndx], 
        [Extent2].[Name] AS [Name], 
        cast(1 as bit) AS [C1]
        FROM [dbo].[Patients] AS [Extent2] ) AS [Project1]
            ON [Extent1].[ndx] = [Project1].[record_ndx]

看起来映射是受尊重的，即Records和Patients表由ndx和record_ndx列连接。

编辑3

重要的是上下文类不包含派生实体的集合，即没有public DbSet<Patient> Patients { get; set; }。如果是这样，则忽略modelBuilder.Entity<Patient>().Property(r => r.Ndx).HasColumnName("record_ndx");映射，EF期望Patient中的主键名是ndx而不是record_ndx。例如，上面SQL的最后一行变成了ON [Extent1].[ndx] = [Project1].[ndx]。