EF Core 2.2，拥有的实体在层次结构中有多个时生成为另一个表

Question

我有一个带有Address标记的类[Owned]和人员层次结构的模型（人员、客户或员工，然后是更多的子类型等）。此层次结构的不同阶段有地址，并且所有地址最终都在一个表中，因为 EF Core 仅限于每个层次结构的表。我希望 address 中的所有属性在那个 person 表中出现多次（在任何子类型中每次提及一次）但是它根本没有出现！相反，我看到每个人的 FK 和一个单独的地址表。

EF Core 是否不支持同一类型的多个拥有成员？如果没有，我应该做什么？我没有任何可能干扰默认值的流畅 API/特定配置（新的空控制台项目，只有配置行是 .UseSQLServer(connectionstring)

示例代码如下：

public class SampleContext : DbContext
{
    public virtual DbSet<Address> Addresses { get; set; }
    public virtual DbSet<Customer> Customers { get; set; }
    public virtual DbSet<Employee> Employees { get; set; }
    public virtual DbSet<Person> Persons { get; set; }

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        if (!optionsBuilder.IsConfigured)
        {
            optionsBuilder.UseSqlServer("my connection string here");
        }
        base.OnConfiguring(optionsBuilder);
    }
}
[Owned]
public class Address
{
    public int Id { get; set; }
    public string AddressLine1 { get; set; }
    public string AddressLine2 { get; set; }
    public string AddressLine3 { get; set; }
    public string City { get; set; }
}

public class Person
{
    public int Id { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public DateTime DateOfBirth { get; set; }
}

public class Employee : Person
{
    public Address Address { get; set; }
}

public class Customer : Person
{
    public Address DeliveryAddress { get; set; }
    public Address InvoicingAddress { get; set; }
}

预期Person表：

DeliveryAddressAddressLine1
DeliveryAddressAddressLine2
DeliveryAddressAddressLine3
DeliveryAddressAddressCity
InvoicingAddressAddressLine1
InvoicingAddressAddressLine2
InvoicingAddressAddressLine3
InvoicingAddressAddressCity
EmployeeAddressAddressLine1
EmployeeAddressAddressLine2
EmployeeAddressAddressLine3
EmployeeAddressAddressCity

生成的Person表（+ 一个意外的Address表）：

EmployeeAddressAddressId
DeliveryAddressAddressId
InvoicingAddressAddressId

编辑：更新了问题，添加了上下文定义并注意到我有Addresses一个 DbSet 所以我认为这可能是原因，删除它会给我以下错误：

不能将表 'Person' 用于实体类型 'Customer.DeliveryAddress#Address'，因为它用于实体类型 'Employee.Address#Address' 并且它们的主键之间没有关系。`

Answer 1

根据 EF Core拥有的实体类型文档：

不支持包含拥有的实体类型的继承层次结构

您可以通过移动克服这个问题 public Address Address { get; set; }，public Address DeliveryAddress { get; set; }并public Address InvoicingAddress { get; set; }从导航属性Employee和Customer基类Person，如下所示：

public class Person
{
    public int Id { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public DateTime DateOfBirth { get; set; }

    public Address Address { get; set; }
    public Address DeliveryAddress { get; set; }
    public Address InvoicingAddress { get; set; }
}

然后使用 fluent API 进行配置以覆盖Navigation_OwnedEntityProperty拥有实体列名称的规则，如下所示：

modelBuilder.Entity<Person>().OwnsOne(p => p.Address,
    a =>
    {
         a.Property(p => p.AddressLine1).HasColumnName("EmployeeAddressLine1");
         a.Property(p => p.AddressLine2).HasColumnName("EmployeeAddressLine2");
         a.Property(p => p.AddressLine2).HasColumnName("EmployeeAddressLine3");
         a.Property(p => p.City).HasColumnName("EmployeeAddressCity");
    }).OwnsOne(p => p.DeliveryAddress,
    a =>
    {
        a.Property(p => p.AddressLine1).HasColumnName("DeliveryAddressLine1");
        a.Property(p => p.AddressLine2).HasColumnName("DeliveryAddressLine2");
        a.Property(p => p.AddressLine2).HasColumnName("DeliveryAddressLine3");
        a.Property(p => p.City).HasColumnName("DeliveryAddressCity");
   }).OwnsOne(p => p.InvoicingAddress,
   a =>
   {
        a.Property(p => p.AddressLine1).HasColumnName("InvoicingAddressLine1");
        a.Property(p => p.AddressLine2).HasColumnName("InvoicingAddressLine2");
        a.Property(p => p.AddressLine2).HasColumnName("InvoicingAddressLine3");
        a.Property(p => p.City).HasColumnName("InvoicingAddressCity");
   });

现在，你，如果你不想动 public Address Address { get; set; }，public Address DeliveryAddress { get; set; }以及public Address InvoicingAddress { get; set; }导航属性从Employee和Customer基类Person，那么你必须创建从每个地址类型不同的表如下：

modelBuilder.Entity<Employee>().OwnsOne(p => p.Address,
    a =>
    {
        a.ToTable("EmployeeAddresses");
    });

modelBuilder.Entity<Customer>().OwnsOne(p => p.DeliveryAddress,
    a =>
    {
        a.ToTable("DeliveryAddresses");
    }).OwnsOne(p => p.InvoicingAddress,
    a =>
    {
        a.ToTable("InvoicingAddresses");
    });