using Microsoft.EntityFrameworkCore;
using System.Collections.Generic;
using Microsoft.Data.SqlClient;
using System.Threading.Tasks;
public static void Main()
public static async Task MainAsync()
using (var context = new EntityContext())
context.Database.EnsureCreated();
var customers = GenerateCustomers(3);
using (var context = new EntityContext())
FiddleHelper.WriteTable("1 - Customers Before", context.Customers.AsNoTracking());
CancellationTokenSource tcs = new CancellationTokenSource();
CancellationToken token = new CancellationToken();
await context.BulkUpdateAsync(customers, options => options.ColumnPrimaryKeyExpression = c => c.Code,token);
FiddleHelper.WriteTable("2 - Customers After", context.Customers.AsNoTracking());
public static List<Customer> GenerateCustomers(int count, bool useOld = false)
List<Customer> list = new List<Customer>();
for(int i = 0; i < count; i++)
list.Add(new Customer() { Code = "Z" + (i + 1), Name = (useOld ? "Old_" : "") + "Customer_" + i});
public static void SeedCustomers(int count)
var customers = GenerateCustomers(count, true);
new EntityContext().BulkInsert(customers);
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 int CustomerID { get; set; }
public string Code { get; set; }
public string Name { get; set; }