entity framework并行一对多关系
我一直在寻找尝试在EF中创建一个并行的一对多关系。 这是我的意思：
我有两个类，交易和用户：
public class Transaction { public int ID { get; set; } public string ExecutorID { get; set; } public virtual User Executor { get; set; } public string ConsumerID { get; set; } public virtual User Consumer { get; set; } } public class User { public UserRole Role { get; set; } public string Name { get; set; } public string Id { get; set; } public string Pin { get; set; } public virtual List ExecutedTransactions { get; set; } public virtual List Transactions { get; set; } } 如果您还没有看到它，我在对象， Transactions和Executed Transactions之间有两个链接。 我的问题是如何告诉EF区分这两者？
事务应该指向User.ID == Transaction.ConsumerID和ExecutedTransactions所有Transaction ，其中User.ID == Transaction.ExecutorID
以下是Food和Book源自Item 。
public class Person { public int Id { get; set; } public string Name { get; set; } public ICollection Foods { get; set; } public ICollection Books { get; set; } } public abstract class Item { public int Id { get; set; } public string Name { get; set; } } public class Food : Item { public int CookedById { get; set; } [ForeignKey("CookedById")] public Person CookedBy { get; set; } } public class Book : Item { public int AuthorId { get; set; } [ForeignKey("AuthorId")] public Person Author { get; set; } }
选项每个层次结构的表
public class AppContext : DbContext { public DbSet People { get; set; } public DbSet- Items { get; set; } protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Entity
().HasMany(p => p.Foods).WithRequired(f => f.CookedBy).WillCascadeOnDelete(false); } }
结果将是2个表 ，表Person和Item具有自动Discriminator列，将填充Food和Book 。
要查询，您需要按类型过滤Items 。
using (var context = new AppContext()) { var foods = context.Items.Where(item => item is Food).ToArray(); var books = context.Items.Where(item => item is Book).ToArray(); }
选项B每个混凝土类别的表格
public class AppContext : DbContext { public DbSet People { get; set; } public DbSet Foods { get; set; } public DbSet Books { get; set; } protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Entity().HasMany(p => p.Foods).WithRequired(f => f.CookedBy).WillCascadeOnDelete(false); } }
结果将是3个表 ，表Person ， Food和Book 。
要查询，您可以直接从食品和书籍。
using (var context = new AppContext()) { var foods = context.Foods.ToArray(); var books = context.Books.ToArray(); }
选项C每种类型的表
public class AppContext : DbContext { public DbSet People { get; set; } public DbSet- Items { get; set; } protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Entity
().HasMany(p => p.Foods).WithRequired(f => f.CookedBy).WillCascadeOnDelete(false); modelBuilder.Entity().ToTable("Foods"); modelBuilder.Entity().ToTable("Books"); } }
结果将是4个表 ，表Person ， Item ， Food和Book 。 Table Food and Book将与表Ttem 。
查询与Table Per Hierarchy相同。