实体框架：分割表到多个表 [英] Entity Framework: Split table into multiple tables
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问题描述
我有以下表[PaymentComponent]使用下面的EF code第一种方法（TPH继承）创建的。它工作正常。我需要改变数据库设计 - 需要存储在GiftCouponPayment表GiftCouponPayments和ClubCardPayments在ClubCardPayment表。需要什么样的变化将在C＃code进行，以获得所需的数据库结构？
code
公共抽象类PaymentComponent
{
公众诠释PaymentComponentID {获得;组; }
公众诠释myvalue的{获得;组; }
公共字符串的MyType {获得;组; }
公共抽象INT GetEffectiveValue（）;
}
公共部分类GiftCouponPayment：PaymentComponent
{
公众覆盖INT GetEffectiveValue（）
{
如果（myvalue的＆所述; 2000）
{
返回0;
}
返回myvalue的;
}
}
公共部分类ClubCardPayment：PaymentComponent
{
公众覆盖INT GetEffectiveValue（）
{
返回myvalue的;
}
}
公共部分类付款
{
公众诠释PaymentID {获得;组; }
公开名单＆LT; PaymentComponent＆GT; PaymentComponents {获得;组; }
公开日期时间PayedTime {获得;组; }
}
//System.Data.Entity.DbContext是EntityFramework.dll
公共类NerdDinners：System.Data.Entity.DbContext
{
公共NerdDinners（字符串CONNSTRING）：基地（CONNSTRING）
{
}
保护覆盖无效OnModelCreating（DbModelBuilder模型构建器）
{
modelbuilder.Conventions.Remove＆其中; PluralizingTableNameConvention＆GT;（）;
}
公共DbSet＆LT; GiftCouponPayment＆GT; GiftCouponPayments {获得;组; }
公共DbSet＆LT; ClubCardPayment＆GT; ClubCardPayments {获得;组; }
公共DbSet＆LT;付款和GT;付款{获得;组; }
}
客户端
静态无效的主要（字串[] args）
{
字符串的ConnectionString =数据源=;初始目录= NerdDinners;集成安全性= TRUE;连接超时= 30;
使用（VAR DB =新NerdDinners（的ConnectionString））
{
GiftCouponPayment giftCouponPayment =新GiftCouponPayment（）;
giftCouponPayment.MyValue = 250;
giftCouponPayment.MyType =GiftCouponPayment;
ClubCardPayment clubCardPayment =新ClubCardPayment（）;
clubCardPayment.MyValue = 5000;
clubCardPayment.MyType =ClubCardPayment;
名单＆LT; PaymentComponent＆GT;谱曲=新的名单，其中，PaymentComponent＆GT;（）;
comps.Add（giftCouponPayment）;
comps.Add（clubCardPayment）;
VAR支付=新的支付{PaymentComponents =谱曲，PayedTime = DateTime.Now};
db.Payments.Add（付款）;
INT recordsAffected = db.SaveChanges（）;
}
}
参考
- <一个href="http://stackoverflow.com/questions/9511021/how-do-i-get-entity-framework-4-3-$c$c-first-to-map-a-subclass-using-table-per-t">How我得到实体框架4.3 code首先要使用每个类型（TPT）映射一个子类？
- <一个href="http://weblogs.asp.net/manavi/archive/2011/04/24/associations-in-ef-4-1-$c$c-first-part-4-table-splitting.aspx" rel="nofollow">http://weblogs.asp.net/manavi/archive/2011/04/24/associations-in-ef-4-1-$c$c-first-part-4-table-splitting.aspx
- 的http://www.robbagby.com/entity-framework/entity-framework-modeling-entity-splitting/
- 在实体框架映射方案 - http://msdn.microsoft.com/en -us /库/ cc716779.aspx
- <一个href="http://blogs.microsoft.co.il/blogs/gilf/archive/2009/03/06/entity-splitting-in-entity-framework.aspx" rel="nofollow">http://blogs.microsoft.co.il/blogs/gilf/archive/2009/03/06/entity-splitting-in-entity-framework.aspx
解决方案
在上下文类OnModelCreating：
modelBuilder.Entity＆LT; GiftCouponPayment＆GT;（）
.MAP（米=＆GT;
{
m.MapInheritedProperties（）;
m.ToTable（GiftCouponPayment）;
}）;
modelBuilder.Entity＆LT; ClubCardPayment＆GT;（）
.MAP（米=＆GT;
{
m.MapInheritedProperties（）;
m.ToTable（ClubCardPayment）;
}）;
I have the following table [PaymentComponent] created using following EF code first approach (TPH inheritance). It works fine. I need to change the database design – need to store GiftCouponPayments in GiftCouponPayment table and ClubCardPayments in ClubCardPayment table. What change need to be done in C# code to get the required database structure?
CODE
public abstract class PaymentComponent
{
public int PaymentComponentID { get; set; }
public int MyValue { get; set; }
public string MyType { get; set; }
public abstract int GetEffectiveValue();
}
public partial class GiftCouponPayment : PaymentComponent
{
public override int GetEffectiveValue()
{
if (MyValue < 2000)
{
return 0;
}
return MyValue;
}
}
public partial class ClubCardPayment : PaymentComponent
{
public override int GetEffectiveValue()
{
return MyValue;
}
}
public partial class Payment
{
public int PaymentID { get; set; }
public List<PaymentComponent> PaymentComponents { get; set; }
public DateTime PayedTime { get; set; }
}
//System.Data.Entity.DbContext is from EntityFramework.dll
public class NerdDinners : System.Data.Entity.DbContext
{
public NerdDinners(string connString): base(connString)
{
}
protected override void OnModelCreating(DbModelBuilder modelbuilder)
{
modelbuilder.Conventions.Remove<PluralizingTableNameConvention>();
}
public DbSet<GiftCouponPayment> GiftCouponPayments { get; set; }
public DbSet<ClubCardPayment> ClubCardPayments { get; set; }
public DbSet<Payment> Payments { get; set; }
}
CLIENT
static void Main(string[] args)
{
string connectionstring = "Data Source=.;Initial Catalog=NerdDinners;Integrated Security=True;Connect Timeout=30";
using (var db = new NerdDinners(connectionstring))
{
GiftCouponPayment giftCouponPayment = new GiftCouponPayment();
giftCouponPayment.MyValue=250;
giftCouponPayment.MyType = "GiftCouponPayment";
ClubCardPayment clubCardPayment = new ClubCardPayment();
clubCardPayment.MyValue = 5000;
clubCardPayment.MyType = "ClubCardPayment";
List<PaymentComponent> comps = new List<PaymentComponent>();
comps.Add(giftCouponPayment);
comps.Add(clubCardPayment);
var payment = new Payment { PaymentComponents = comps, PayedTime=DateTime.Now };
db.Payments.Add(payment);
int recordsAffected = db.SaveChanges();
}
}
REFERENCE:
- How do I get Entity Framework 4.3 Code First to map a subclass using Table Per Type (TPT)?
- http://weblogs.asp.net/manavi/archive/2011/04/24/associations-in-ef-4-1-code-first-part-4-table-splitting.aspx
- http://www.robbagby.com/entity-framework/entity-framework-modeling-entity-splitting/
- Entity Framework Mapping Scenarios - http://msdn.microsoft.com/en-us/library/cc716779.aspx
- http://blogs.microsoft.co.il/blogs/gilf/archive/2009/03/06/entity-splitting-in-entity-framework.aspx
解决方案
In your Context class in OnModelCreating:
modelBuilder.Entity<GiftCouponPayment>()
.Map(m =>
{
m.MapInheritedProperties();
m.ToTable("GiftCouponPayment");
});
modelBuilder.Entity<ClubCardPayment>()
.Map(m =>
{
m.MapInheritedProperties();
m.ToTable("ClubCardPayment");
});
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