一对一成为一对多实体框架，首先生成数据库

Question

我首先生成Entity Framework数据库（数据库中的EF Designer）。我在Microsoft SQL Server中有两个表：

CREATE TABLE dbo.Person
(
    Pk_Person_Id INT IDENTITY PRIMARY KEY,
    Name VARCHAR(255),
    EmailId VARCHAR(255),
);

CREATE TABLE dbo.PassportDetails
(
    Pk_Passport_Id INT PRIMARY KEY,
    Passport_Number VARCHAR(255),
    Fk_Person_Id INT UNIQUE 
       FOREIGN KEY REFERENCES dbo.Person(Pk_Person_Id)
);

INSERT INTO dbo.Person 
VALUES ('Niraj','v.a@emails.com'),
       ('Vishwanath','v.v@emails.com'),
       ('Chetan','c.v@emails.com');
GO

INSERT INTO dbo.PassportDetails 
VALUES (101, 'C3031R33', 1), (102, 'VRDK5695', 2), (103, 'A4DEK33D', 3);
GO

SELECT * FROM dbo.Person
SELECT * FROM dbo.PassportDetails;

在SQL Server中，关系显示为一对一，因为Fk_Person_Id设置为isUnique = true：

Fk_Person_Id INT UNIQUE 
     FOREIGN KEY REFERENCES dbo.Person(Pk_Person_Id));

现在在Visual Studio中，我添加一个新的ADO.NET实体数据模型->数据库中的EF设计器->选择这两个表，并默认保留所有复选框选项。

然后生成结束，我在Visual Studio图.edmx中看到了这一点：

这种关系一对多发生了变化-为什么？这是错的吗？我不想让一个人拥有护照-这不是我要描述的逻辑。

以及EF代码：

public partial class Person
{
    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]
    public Person()
    {
        this.PassportDetails = new HashSet<PassportDetail>();
    }

    public int Pk_Person_Id { get; set; }
    public string Name { get; set; }
    public string EmailId { get; set; }

    [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
    public virtual ICollection<PassportDetail> PassportDetails { get; set; }
}

public partial class PassportDetail
{
    public int Pk_Passport_Id { get; set; }
    public string Passport_Number { get; set; }
    public Nullable<int> Fk_Person_Id { get; set; }

    public virtual Person Person { get; set; }
}

上下文

public partial class LightCRMEntities : DbContext
{
    public LightCRMEntities() : base("name=LightCRMEntities")
    {
    }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        throw new UnintentionalCodeFirstException();
    }

    public virtual DbSet<PassportDetail> PassportDetails { get; set; }
    public virtual DbSet<Person> People { get; set; }
}

Answer 1

好吧，在数据库模型编辑器（.edmx文件编辑器）中，通过单击一个关系（实体图元之间的箭头），可以以这种方式配置它的属性，以使其一对一（它不会更改您的数据库！），但是随后您可以生成创建此类数据库所需的代码。结果，我得到以下信息：

-- --------------------------------------------------
-- Creating all tables
-- --------------------------------------------------

-- Creating table 'PassportDetails'
CREATE TABLE [dbo].[PassportDetails] (
    [Pk_Passport_Id] int  NOT NULL,
    [Passport_Number] varchar(255)  NULL
);
GO

-- Creating table 'Person'
CREATE TABLE [dbo].[Person] (
    [Pk_Person_Id] int IDENTITY(1,1) NOT NULL,
    [Name] varchar(255)  NULL,
    [EmailId] varchar(255)  NULL
);
GO

-- --------------------------------------------------
-- Creating all PRIMARY KEY constraints
-- --------------------------------------------------

-- Creating primary key on [Pk_Passport_Id] in table 'PassportDetails'
ALTER TABLE [dbo].[PassportDetails]
ADD CONSTRAINT [PK_PassportDetails]
    PRIMARY KEY CLUSTERED ([Pk_Passport_Id] ASC);
GO

-- Creating primary key on [Pk_Person_Id] in table 'Person'
ALTER TABLE [dbo].[Person]
ADD CONSTRAINT [PK_Person]
    PRIMARY KEY CLUSTERED ([Pk_Person_Id] ASC);
GO

-- --------------------------------------------------
-- Creating all FOREIGN KEY constraints
-- --------------------------------------------------

-- Creating foreign key on [Pk_Passport_Id] in table 'PassportDetails'
ALTER TABLE [dbo].[PassportDetails]
ADD CONSTRAINT [FK__PassportD__Pk_Pa__5BE2A6F2]
    FOREIGN KEY ([Pk_Passport_Id])
    REFERENCES [dbo].[Person]
        ([Pk_Person_Id])
    ON DELETE NO ACTION ON UPDATE NO ACTION;
GO