// Entity Framework Extensions

// Doc: https://entityframework-extensions.net/bulk-synchronize

​

// @nuget: Microsoft.EntityFrameworkCore.SqlServer

// @nuget: Z.EntityFramework.Extensions.EFCore

​

using Microsoft.EntityFrameworkCore;

using System.Collections.Generic;

using Microsoft.Data.SqlClient;

​

public class Program

{

    public static void Main()

    {

        using (var context = new EntityContext())

        {

            context.Database.EnsureCreated();

        }

        GenerateCustomers(3);

        var customizeToSynchronize = new List<Customer>();

        for(int i = 0; i < 2; i++)

        {

            customizeToSynchronize.Add(new Customer() { Code = "Code_" + i, FirstName = "Updated_FirstName_" + i, LastName = "Updated_LastName_" + i });

        }

        for(int i = 0; i < 2; i++)

        {

            customizeToSynchronize.Add(new Customer() { CustomerID = 1000 + i, Code = "New_Code_" + i, FirstName = "New_FirstName_" + i, LastName = "New_LastName_" + i });

        }

        using (var context = new EntityContext())

        {

            FiddleHelper.WriteTable("1 - Customers Before", context.Customers.AsNoTracking());

            // Easy to use, easy to customize

            context.BulkSynchronize(customizeToSynchronize, options => {

                options.ColumnPrimaryKeyExpression = customer => customer.Code;

                options.SynchronizeKeepidentity = true;

            });

            FiddleHelper.WriteTable("2 - Customers After", context.Customers.AsNoTracking());

        }

    }

    public static List<Customer> GenerateCustomers(int count)

    {

        var list = new List<Customer>();

        for(int i = 0; i < count; i++)

        {

            list.Add(new Customer() { Code = "Code_" + i, FirstName = "FirstName_" + i, LastName = "LastName_" + i });

        }

        using (var context = new EntityContext())

        {

            context.BulkInsert(list);

        }

        return list;

    }

​

    public class EntityContext : DbContext

    {

        public EntityContext() 

        {

        }

​

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)

        {

            optionsBuilder.UseSqlServer(new SqlConnection(FiddleHelper.GetConnectionStringSqlServer()));

​

            base.OnConfiguring(optionsBuilder);

        }

        public DbSet<Customer> Customers { get; set; }

    }

    public class Customer

    {

        public int CustomerID { get; set; }

        public string Code { get; set; }

        public string FirstName { get; set; }

        public string LastName { get; set; }

    }

}