EntityTypeConfiguration issues

Configurations.cs

public class CouponActionMap : EntityTypeConfiguration<CouponAction>
{
    public CouponActionMap()
    {
        ToTable("CouponAction");
    }
}

public class CouponMap : EntityTypeConfiguration<Coupon>
{
    public CouponMap()
    {
        ToTable("Coupon");
        HasRequired(c => c.Action);
    }
}

public class DiscountSchemeActionMap : EntityTypeConfiguration<DiscountSchemeAction>
{
    public DiscountSchemeActionMap()
    {
        ToTable("DiscountSchemeAction");
    }
}

public class DiscountSchemeMap : EntityTypeConfiguration<DiscountScheme>
{
    public DiscountSchemeMap()
    {
        ToTable("DiscountScheme");

        HasRequired(ds => ds.Action);
    }
}

Models.cs

public enum CouponFormula
{

}
public class CouponAction
{
    public int Id { get; set; }
    public int CouponId { get; set; }
    public CouponFormula Formula { get; set; }
    public string Fields { get; set; }
    public virtual Coupon Coupon { get; set; }
}

public enum CouponUsage
{
    PerPerson,
    PerOrder
}

public class Coupon
{
    public int Id { get; set; }
    public bool GlobalMembershipRequired { get; set; }
    public bool ProgramMembershipRequired { get; set; }
    public ProgramType ProgramTypeRequired { get; set; }
    public string Code { get; set; }
    public DateTime? StartDate { get; set; }
    public DateTime? EndDate { get; set; }
    public int? Limit { get; set; }
    public int Used { get; set; }
    public CouponUsage Usage { get; set; }
    public virtual CouponAction Action { get; set; }
}

public enum DiscountSchemeFormula
{

}

public class DiscountSchemeAction
{
    public int Id { get; set; }
    public int DiscountSchemeId { get; set; }
    public DiscountSchemeFormula Formula { get; set; }
    public string Fields { get; set; }
    public virtual DiscountScheme DiscountScheme { get; set; }
}

public enum ApplySchemeScheme
{
    All,
    Any
}

public class DiscountScheme
{
    public int Id { get; set; }
    public string Name { get; set; }
    public ApplySchemeScheme ApplyScheme { get; set; }
    public virtual DiscountSchemeAction Action { get; set; }
}

Queries.sql

-- Coupon
SELECT 
    [Project1].[Id] AS [Id], 
    [Project1].[MembershipPlanId] AS [MembershipPlanId], 
    [Project1].[EventId] AS [EventId], 
    [Project1].[GlobalMembershipRequired] AS [GlobalMembershipRequired], 
    [Project1].[ProgramMembershipRequired] AS [ProgramMembershipRequired], 
    [Project1].[ProgramTypeRequired] AS [ProgramTypeRequired], 
    [Project1].[Code] AS [Code], 
    [Project1].[StartDate] AS [StartDate], 
    [Project1].[EndDate] AS [EndDate], 
    [Project1].[Limit] AS [Limit], 
    [Project1].[Used] AS [Used], 
    [Project1].[Usage] AS [Usage], 
    [Project1].[DateCreated] AS [DateCreated], 
    [Project1].[DateUpdated] AS [DateUpdated], 
    [Project1].[Id1] AS [Id1], 
    [Project1].[CouponId] AS [CouponId], 
    [Project1].[Formula] AS [Formula], 
    [Project1].[Fields] AS [Fields], 
    [Project1].[DateCreated2] AS [DateCreated2], 
    [Project1].[DateUpdated2] AS [DateUpdated2]
    FROM ( SELECT 
        [Extent1].[Id] AS [Id], 
        [Extent1].[MembershipPlanId] AS [MembershipPlanId], 
        [Extent1].[EventId] AS [EventId], 
        [Extent1].[GlobalMembershipRequired] AS [GlobalMembershipRequired], 
        [Extent1].[ProgramMembershipRequired] AS [ProgramMembershipRequired], 
        [Extent1].[ProgramTypeRequired] AS [ProgramTypeRequired], 
        [Extent1].[Code] AS [Code], 
        [Extent1].[StartDate] AS [StartDate], 
        [Extent1].[EndDate] AS [EndDate], 
        [Extent1].[Limit] AS [Limit], 
        [Extent1].[Used] AS [Used], 
        [Extent1].[Usage] AS [Usage], 
        [Extent1].[DateCreated] AS [DateCreated], 
        [Extent1].[DateUpdated] AS [DateUpdated], 
        [Extent3].[Id] AS [Id1], 
        [Extent3].[CouponId] AS [CouponId], 
        [Extent3].[Formula] AS [Formula], 
        [Extent3].[Fields] AS [Fields], 
        [Extent3].[DateCreated] AS [DateCreated2], 
        [Extent3].[DateUpdated] AS [DateUpdated2]
        FROM     [dbo].[Coupon] AS [Extent1]
        INNER JOIN [dbo].[CouponAction] AS [Extent3] ON [Extent1].[Id] = [Extent3].[Id]
    )  AS [Project1]
    ORDER BY [Project1].[Id] ASC, [Project1].[Id1] ASC
    
-- Coupon Action
SELECT 
    [Extent1].[Id] AS [Id], 
    [Extent1].[CouponId] AS [CouponId], 
    [Extent1].[Formula] AS [Formula], 
    [Extent1].[Fields] AS [Fields], 
    [Extent1].[DateCreated] AS [DateCreated], 
    [Extent1].[DateUpdated] AS [DateUpdated], 
    [Extent2].[Id] AS [Id1], 
    [Extent2].[MembershipPlanId] AS [MembershipPlanId], 
    [Extent2].[EventId] AS [EventId], 
    [Extent2].[GlobalMembershipRequired] AS [GlobalMembershipRequired], 
    [Extent2].[ProgramMembershipRequired] AS [ProgramMembershipRequired], 
    [Extent2].[ProgramTypeRequired] AS [ProgramTypeRequired], 
    [Extent2].[Code] AS [Code], 
    [Extent2].[StartDate] AS [StartDate], 
    [Extent2].[EndDate] AS [EndDate], 
    [Extent2].[Limit] AS [Limit], 
    [Extent2].[Used] AS [Used], 
    [Extent2].[Usage] AS [Usage], 
    [Extent2].[DateCreated] AS [DateCreated1], 
    [Extent2].[DateUpdated] AS [DateUpdated1]
    FROM  [dbo].[CouponAction] AS [Extent1]
    LEFT OUTER JOIN [dbo].[Coupon] AS [Extent2] ON [Extent1].[Id] = [Extent2].[Id]
    
-- Discount Scheme
SELECT 
    [Project1].[Id] AS [Id], 
    [Project1].[MembershipPlanId] AS [MembershipPlanId], 
    [Project1].[EventId] AS [EventId], 
    [Project1].[Name] AS [Name], 
    [Project1].[ApplyScheme] AS [ApplyScheme], 
    [Project1].[DateCreated] AS [DateCreated], 
    [Project1].[DateUpdated] AS [DateUpdated], 
    [Project1].[Id1] AS [Id1], 
    [Project1].[DiscountSchemeId] AS [DiscountSchemeId], 
    [Project1].[Formula] AS [Formula], 
    [Project1].[Fields] AS [Fields], 
    [Project1].[DateCreated2] AS [DateCreated2], 
    [Project1].[DateUpdated2] AS [DateUpdated2]
    FROM ( SELECT 
        [Extent1].[Id] AS [Id], 
        [Extent1].[MembershipPlanId] AS [MembershipPlanId], 
        [Extent1].[EventId] AS [EventId], 
        [Extent1].[Name] AS [Name], 
        [Extent1].[ApplyScheme] AS [ApplyScheme], 
        [Extent1].[DateCreated] AS [DateCreated], 
        [Extent1].[DateUpdated] AS [DateUpdated], 
        [Extent3].[Id] AS [Id1], 
        [Extent3].[DiscountSchemeId] AS [DiscountSchemeId], 
        [Extent3].[Formula] AS [Formula], 
        [Extent3].[Fields] AS [Fields], 
        [Extent3].[DateCreated] AS [DateCreated2], 
        [Extent3].[DateUpdated] AS [DateUpdated2]
        FROM     [dbo].[DiscountScheme] AS [Extent1]
        INNER JOIN [dbo].[DiscountSchemeAction] AS [Extent3] ON [Extent1].[Id] = [Extent3].[Id]
    )  AS [Project1]
    ORDER BY [Project1].[Id] ASC, [Project1].[Id1] ASC
    
-- Discount Scheme
SELECT 
    [Extent1].[Id] AS [Id], 
    [Extent1].[DiscountSchemeId] AS [DiscountSchemeId], 
    [Extent1].[Formula] AS [Formula], 
    [Extent1].[Fields] AS [Fields], 
    [Extent1].[DateCreated] AS [DateCreated], 
    [Extent1].[DateUpdated] AS [DateUpdated], 
    [Extent2].[Id] AS [Id1], 
    [Extent2].[MembershipPlanId] AS [MembershipPlanId], 
    [Extent2].[EventId] AS [EventId], 
    [Extent2].[Name] AS [Name], 
    [Extent2].[ApplyScheme] AS [ApplyScheme], 
    [Extent2].[DateCreated] AS [DateCreated1], 
    [Extent2].[DateUpdated] AS [DateUpdated1]
    FROM  [dbo].[DiscountSchemeAction] AS [Extent1]
    LEFT OUTER JOIN [dbo].[DiscountScheme] AS [Extent2] ON [Extent1].[Id] = [Extent2].[Id]

Tables.sql

CREATE TABLE [dbo].[Coupon]
(
[Id] [int] NOT NULL IDENTITY(1, 1),
[Name] [nvarchar] (max) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,
[Code] [nvarchar] (max) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,
[GlobalMembershipRequired] [bit] NOT NULL,
[ProgramMembershipRequired] [bit] NOT NULL,
[ProgramTypeRequired] [int] NOT NULL CONSTRAINT [DF_Coupon_ProgramTypeRequired] DEFAULT ((0)),
[StartDate] [datetime] NULL,
[EndDate] [datetime] NULL,
[Limit] [int] NULL,
[Used] [int] NOT NULL CONSTRAINT [DF_Coupon_Used] DEFAULT ((0)),
[Usage] [int] NOT NULL CONSTRAINT [DF_Coupon_Usage] DEFAULT ((0)),
[DateCreated] [datetime] NOT NULL CONSTRAINT [DF_Coupon_DateCreated] DEFAULT (getdate()),
[DateUpdated] [datetime] NULL
) ON [PRIMARY]
GO
ALTER TABLE [dbo].[Coupon] ADD CONSTRAINT [PK_Coupon] PRIMARY KEY CLUSTERED  ([Id]) ON [PRIMARY]
GO

CREATE TABLE [dbo].[CouponAction]
(
[Id] [int] NOT NULL IDENTITY(1, 1),
[CouponId] [int] NOT NULL,
[Formula] [int] NOT NULL,
[Fields] [nvarchar] (max) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,
[DateCreated] [datetime] NOT NULL CONSTRAINT [DF_CouponAction_DateCreated] DEFAULT (getdate()),
[DateUpdated] [datetime] NULL
) ON [PRIMARY]
GO
ALTER TABLE [dbo].[CouponAction] ADD CONSTRAINT [PK_CouponAction] PRIMARY KEY CLUSTERED  ([Id]) ON [PRIMARY]
GO
ALTER TABLE [dbo].[CouponAction] ADD CONSTRAINT [FK_CouponAction_Coupon] FOREIGN KEY ([CouponId]) REFERENCES [dbo].[Coupon] ([Id])
GO

CREATE TABLE [dbo].[DiscountScheme]
(
[Id] [int] NOT NULL IDENTITY(1, 1),
[Name] [nvarchar] (max) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,
[ApplyScheme] [int] NOT NULL,
[DateCreated] [datetime] NOT NULL CONSTRAINT [DF_DiscountScheme_DateCreated] DEFAULT (getdate()),
[DateUpdated] [datetime] NULL
) ON [PRIMARY]
GO
ALTER TABLE [dbo].[DiscountScheme] ADD CONSTRAINT [PK_DiscountScheme] PRIMARY KEY CLUSTERED  ([Id]) ON [PRIMARY]
GO

CREATE TABLE [dbo].[DiscountSchemeAction]
(
[Id] [int] NOT NULL IDENTITY(1, 1),
[DiscountSchemeId] [int] NOT NULL,
[Formula] [int] NOT NULL,
[Fields] [nvarchar] (max) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL,
[DateCreated] [datetime] NOT NULL CONSTRAINT [DF_DiscountSchemeAction_DateCreated] DEFAULT (getdate()),
[DateUpdated] [datetime] NULL
) ON [PRIMARY]
GO
ALTER TABLE [dbo].[DiscountSchemeAction] ADD CONSTRAINT [PK_DiscountSchemeAction] PRIMARY KEY CLUSTERED  ([Id]) ON [PRIMARY]
GO
ALTER TABLE [dbo].[DiscountSchemeAction] ADD CONSTRAINT [FK_DiscountSchemeAction_DiscountScheme] FOREIGN KEY ([DiscountSchemeId]) REFERENCES [dbo].[DiscountScheme] ([Id])
GO