using System.Data.Entity;
using System.Collections.Generic;
public static void Main()
var invoices = GenerateInvoices(5, 3);
var items = invoices.SelectMany(x => x.Items);
using (var context = new EntityContext())
context.BulkInsert(invoices);
context.BulkInsert(items);
Console.WriteLine("An error is throw because the Invoice relation cannot be found.");
context.Invoices.AddRange(invoices);
context.BulkInsert(items);
FiddleHelper.WriteTable("2 - Invoices", context.Invoices);
FiddleHelper.WriteTable("3 - InvoiceItems", context.InvoiceItems);
public static List<Invoice> GenerateInvoices(int countInvoice, int countInvoiceItem)
List<Invoice> list = new List<Invoice>();
for(int i = 0; i < countInvoice; i++)
var invoice = new Invoice() { Number = "Number_" + i, Items = new List<InvoiceItem>() };
for(int j = 0; j < countInvoiceItem; j++)
invoice.Items.Add(new InvoiceItem() { ProductName = "ProductName_" + i + "_" + j });
public class EntityContext : DbContext
public EntityContext() : base(FiddleHelper.GetConnectionStringSqlServer())
public DbSet<Invoice> Invoices { get; set; }
public DbSet<InvoiceItem> InvoiceItems { get; set; }
public int InvoiceID { get; set; }
public string Number { get; set; }
public List<InvoiceItem> Items { get; set; }
public int InvoiceItemID { get; set; }
public string ProductName { get; set; }