using Microsoft.EntityFrameworkCore;
using System.Collections.Generic;
using Microsoft.Data.SqlClient;
public static void Main()
using (var context = new EntityContext())
context.Database.EnsureCreated();
var customers = GenerateCustomers(5);
var invoices = GenerateInvoices(5, 3);
using (var context = new EntityContext())
context.BulkInsert(customers);
context.BulkInsert(invoices, options => options.IncludeGraph = true);
FiddleHelper.WriteTable("1 - Customers", context.Customers);
FiddleHelper.WriteTable("2 - Invoices", context.Invoices);
FiddleHelper.WriteTable("3 - InvoiceItems", context.InvoiceItems);
public static List<Customer> GenerateCustomers(int count)
List<Customer> list = new List<Customer>();
for(int i = 0; i < count; i++)
list.Add(new Customer() { Name = "Customer_" + i});
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
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
optionsBuilder.UseSqlServer(new SqlConnection(FiddleHelper.GetConnectionStringSqlServer()));
base.OnConfiguring(optionsBuilder);
public DbSet<Customer> Customers { get; set; }
public DbSet<Invoice> Invoices { get; set; }
public DbSet<InvoiceItem> InvoiceItems { get; set; }
public int CustomerID { get; set; }
public string Name { 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; }
public Invoice Invoice { get; set; }