我想通过代码优先实现TPC映射,我读过这篇文章: Inheritance with EF Code First: Part 3 – Table per Concrete Type (TPC)
我已经编写了如下代码。
namespace TPCTest
{
class Program
{
static void Main(string[] args)
{
using (TestContext context = new TestContext())
{
Manager m = new Manager();
m.AnnualSalary = 100000;
m.Name = "Allen";
m.Sex = true;
m.Id = 1;
Worker w = new Worker();
w.Id = 2;
w.Name = "John";
w.Sex = true;
w.MonthlyPay = 5000;
context.empSet.Add(m);
context.empSet.Add(w);
context.SaveChanges();
}
}
}
abstract class Employee
{
public int Id { get; set; }
public string Name { get; set; }
public bool Sex { get; set; }
}
class Manager : Employee
{
public decimal AnnualSalary { get; set; }
public string Department { get; set; }
}
class Worker : Employee
{
public decimal MonthlyPay { get; set; }
}
class TestContext : DbContext
{
public DbSet<Employee> empSet { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Manager>().Map(m =>
{
m.MapInheritedProperties();
m.ToTable("Manager");
});
modelBuilder.Entity<Worker>().Map(m =>
{
m.MapInheritedProperties();
m.ToTable("Worker");
});
modelBuilder.Entity<Employee>().Property(e => e.Id).HasDatabaseGeneratedOption(System.ComponentModel.DataAnnotations.DatabaseGeneratedOption.None);
}
}
}
但是在运行代码之后,我发现Employee表也存在于数据库中,任何人都可以提供帮助吗?
提前致谢!
答案 0 :(得分:0)
使用EF 5.0或更高版本!
自该版本以来,该问题似乎已得到解决。使用EF 4.3.1,我可以重现行为。所以只需更新。