global.json

{
  "projects": ["c:/source/entityframework/src"]
}

MyContext.cs

using Microsoft.Data.Entity;

namespace ConsoleApp1
{
    public class MyContext : DbContext
    {
        public DbSet<Address> Addresses { get; set; }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            optionsBuilder.UseSqlServer("Server=localhost\\sqlexpress;Database=rep2057;Trusted_Connection=True;MultipleActiveResultSets=true");
        }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.Model.AddEntityType(typeof(CustomerAddress));
            modelBuilder.Model.AddEntityType(typeof(EmployeeAddress));

            var address = modelBuilder.Entity<Address>();
            address.Key(x => x.Id);
            address.Metadata.Relational().DiscriminatorProperty = address.Property(x => x.Discriminator).Metadata;

            var customer = modelBuilder.Entity<CustomerAddress>().Metadata;
            customer.BaseType = modelBuilder.Model.GetEntityType(typeof(Address));
            customer.Relational().DiscriminatorValue = Discriminator.CustomerAddress;

            var employee = modelBuilder.Entity<EmployeeAddress>().Metadata;
            employee.BaseType = modelBuilder.Model.GetEntityType(typeof(Address));
            employee.Relational().DiscriminatorValue = Discriminator.EmployeeAddress;
        }
    }
}

Program.cs

using System;
using System.Diagnostics;
using System.Linq;
using Microsoft.Framework.DependencyInjection;
using Microsoft.Framework.Logging;

namespace ConsoleApp1
{
    public class Program
    {
        public void Main(string[] args)
        {
            var logger = new SimpleLoggerFactory();

            var serviceCollection = new ServiceCollection();
            serviceCollection
                .AddInstance<ILoggerFactory>(logger)
                .AddEntityFramework()
                .AddSqlServer()
                .AddDbContext<MyContext>();

            var provider = serviceCollection.BuildServiceProvider();

            using (var _db = provider.GetService<MyContext>())
            {
//                _db.Database.AsRelational().EnsureCreated();
                var result = _db.Addresses.Where(x => x.Discriminator == Discriminator.CustomerAddress).ToList();
                Console.WriteLine(result.Count);
            }
            //var sql = logger.Instance.Sb.ToString();
            //Console.WriteLine(sql);
            //Debug.Assert(sql.Contains("@__p_0: 1"));
            //Console.ReadLine();
        }
    }

    public abstract class Address
    {
        public int Id { get; set; }
        public Discriminator Discriminator { get; private set; }

        private Address()
        {

        }

        protected Address(Discriminator discriminator)
        {
            Discriminator = discriminator;
        }
    }

    public class CustomerAddress : Address
    {
        public CustomerAddress()
            : base(Discriminator.CustomerAddress)
        {

        }
    }

    public class EmployeeAddress : Address
    {
        public EmployeeAddress()
            : base(Discriminator.EmployeeAddress)
        {

        }
    }

    public enum Discriminator
    {
        CustomerAddress = 1,
        EmployeeAddress = 2
    }
}

project.json

{
  "version": "1.0.0-*",
  "description": "",
  "authors": [ "" ],
  "tags": [ "" ],
  "projectUrl": "",
  "licenseUrl": "",

  "dependencies": {
    "EntityFramework.SqlServer": "7.0.0-*"
  },

  "commands": {
    "ConsoleApp1" : "ConsoleApp1"
  },

  "frameworks" : {
    "dnx451": { }
  }
}

reproduce2057.sln


Microsoft Visual Studio Solution File, Format Version 12.00
# Visual Studio 14
VisualStudioVersion = 14.0.22823.1
MinimumVisualStudioVersion = 10.0.40219.1
Project("{8BB2217D-0F2D-49D1-97BC-3654ED321F3B}") = "reproduce2057", "reproduce2057.xproj", "{171473B3-CFDC-4743-A0C9-40B0A1388D79}"
EndProject
Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution Items", "{2EC230E8-C618-4FC4-BA0D-8A1B958B54D5}"
	ProjectSection(SolutionItems) = preProject
		global.json = global.json
	EndProjectSection
EndProject
Project("{8BB2217D-0F2D-49D1-97BC-3654ED321F3B}") = "EntityFramework.SqlServer", "..\entityframework\src\EntityFramework.SqlServer\EntityFramework.SqlServer.xproj", "{1ACE01A3-97E2-41A7-A315-4AE53E53794E}"
EndProject
Project("{8BB2217D-0F2D-49D1-97BC-3654ED321F3B}") = "EntityFramework.Relational", "..\entityframework\src\EntityFramework.Relational\EntityFramework.Relational.xproj", "{AD2D13EB-AA07-45FB-B946-1F61CCC0D9F7}"
EndProject
Project("{8BB2217D-0F2D-49D1-97BC-3654ED321F3B}") = "EntityFramework.Core", "..\entityframework\src\EntityFramework.Core\EntityFramework.Core.xproj", "{CE8F7D9C-FAC7-4BA9-868F-47A8BA3C381B}"
EndProject
Global
	GlobalSection(SolutionConfigurationPlatforms) = preSolution
		Debug|Any CPU = Debug|Any CPU
		Release|Any CPU = Release|Any CPU
	EndGlobalSection
	GlobalSection(ProjectConfigurationPlatforms) = postSolution
		{171473B3-CFDC-4743-A0C9-40B0A1388D79}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
		{171473B3-CFDC-4743-A0C9-40B0A1388D79}.Debug|Any CPU.Build.0 = Debug|Any CPU
		{171473B3-CFDC-4743-A0C9-40B0A1388D79}.Release|Any CPU.ActiveCfg = Release|Any CPU
		{171473B3-CFDC-4743-A0C9-40B0A1388D79}.Release|Any CPU.Build.0 = Release|Any CPU
		{1ACE01A3-97E2-41A7-A315-4AE53E53794E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
		{1ACE01A3-97E2-41A7-A315-4AE53E53794E}.Debug|Any CPU.Build.0 = Debug|Any CPU
		{1ACE01A3-97E2-41A7-A315-4AE53E53794E}.Release|Any CPU.ActiveCfg = Release|Any CPU
		{1ACE01A3-97E2-41A7-A315-4AE53E53794E}.Release|Any CPU.Build.0 = Release|Any CPU
		{AD2D13EB-AA07-45FB-B946-1F61CCC0D9F7}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
		{AD2D13EB-AA07-45FB-B946-1F61CCC0D9F7}.Debug|Any CPU.Build.0 = Debug|Any CPU
		{AD2D13EB-AA07-45FB-B946-1F61CCC0D9F7}.Release|Any CPU.ActiveCfg = Release|Any CPU
		{AD2D13EB-AA07-45FB-B946-1F61CCC0D9F7}.Release|Any CPU.Build.0 = Release|Any CPU
		{CE8F7D9C-FAC7-4BA9-868F-47A8BA3C381B}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
		{CE8F7D9C-FAC7-4BA9-868F-47A8BA3C381B}.Debug|Any CPU.Build.0 = Debug|Any CPU
		{CE8F7D9C-FAC7-4BA9-868F-47A8BA3C381B}.Release|Any CPU.ActiveCfg = Release|Any CPU
		{CE8F7D9C-FAC7-4BA9-868F-47A8BA3C381B}.Release|Any CPU.Build.0 = Release|Any CPU
	EndGlobalSection
	GlobalSection(SolutionProperties) = preSolution
		HideSolutionNode = FALSE
	EndGlobalSection
EndGlobal

reproduce2057.xproj

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="__ToolsVersion__" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <PropertyGroup>
    <VisualStudioVersion Condition="'$(VisualStudioVersion)' == ''">14.0</VisualStudioVersion>
    <VSToolsPath Condition="'$(VSToolsPath)' == ''">$(MSBuildExtensionsPath32)\Microsoft\VisualStudio\v$(VisualStudioVersion)</VSToolsPath>
  </PropertyGroup>
  <Import Project="$(VSToolsPath)\DNX\Microsoft.DNX.Props" Condition="'$(VSToolsPath)' != ''" />
  <PropertyGroup Label="Globals">
    <ProjectGuid>171473b3-cfdc-4743-a0c9-40b0a1388d79</ProjectGuid>
  </PropertyGroup>

  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x86'" Label="Configuration">
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x86'" Label="Configuration">
  </PropertyGroup>
  <PropertyGroup>
    <SchemaVersion>2.0</SchemaVersion>
  </PropertyGroup>
  <Import Project="$(VSToolsPath)\DNX\Microsoft.DNX.targets" Condition="'$(VSToolsPath)' != ''" />
</Project>

SimpleLoggerFactory.cs

using System;
using System.Text;
using Microsoft.Framework.Logging;

namespace ConsoleApp1
{
    public class SimpleLoggerFactory : ILoggerFactory
    {
        public SimpleLogger Instance { get; } = new SimpleLogger();

        public ILogger CreateLogger(string categoryName)
        {
            return Instance;
        }

        public void AddProvider(ILoggerProvider provider)
        {
        }

        public LogLevel MinimumLevel { get; set; }

        public class SimpleLogger : ILogger
        {
            public StringBuilder Sb { get; } = new StringBuilder();

            public void Log(LogLevel logLevel, int eventId, object state, Exception exception,
                Func<object, Exception, string> formatter)
            {
                if (formatter == null || eventId != 42)
                    return;
                Sb.AppendLine(formatter(state, exception));
            }

            public bool IsEnabled(LogLevel logLevel) => true;

            public IDisposable BeginScopeImpl(object state)
            {
                return new NullScope();
            }

            public class NullScope : IDisposable
            {
                public void Dispose()
                {
                }
            }
        }
    }
}