// Entity Framework Extensions

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

​

// @nuget: Z.EntityFramework.Extensions

// @nuget: EntityFramework

​

using System;

using System.Collections.Generic;

using System.Diagnostics;

using System.Data.Entity;

using System.Linq;

using System.Data.Entity.Migrations;

​

public class Program

{

    public static List<BenchmarkResult> BenchmarkResults = new List<BenchmarkResult>();

    public static void Main()

    {

        JustInTime_Compile();

        var customerCount = 500;

​

        var clockSaveChanges = new Stopwatch();

        var clockBulkMerge = new Stopwatch();

        using (var context = new EntityContext())

        {

​

            // Clean

            context.BulkDelete(context.Customers);

            // Generate X customers (half for update, half for insert)

            var customers = GenerateCustomers(customerCount).ToArray();

            customers.ToList().ForEach(x => x.FirstName += "_z");

​

            // AddOrUpdate + SaveChanges

            clockSaveChanges.Start();

            context.Customers.AddOrUpdate(customers);

            context.SaveChanges();

            clockSaveChanges.Stop();

​

            BenchmarkResults.Add(new BenchmarkResult() { Action = "SaveChanges (EF)", Entities = customers.Length, Performance = clockSaveChanges.ElapsedMilliseconds + " ms" });

        }

        using (var context = new EntityContext())

        {

            // Clean

            context.BulkDelete(context.Customers);

            // Generate X customers (half for update, half for insert)

            var customers = GenerateCustomers(customerCount).ToArray();     

            customers.ToList().ForEach(x => x.FirstName += "_z");

​

            // BulkMerge

            clockBulkMerge.Start();

            context.BulkMerge(customers);

            clockBulkMerge.Stop();

​

            BenchmarkResults.Add(new BenchmarkResult() { Action = "BulkMerge (EF Extensions)", Entities = customers.Length, Performance = clockBulkMerge.ElapsedMilliseconds + " ms" });

            // Clean

            context.BulkDelete(context.Customers);

        }

        FiddleHelper.WriteTable(BenchmarkResults);

    }

    public static void JustInTime_Compile()

    {

        // SaveChanges

        using (var context = new EntityContext())

        {

            var customers = context.Customers.AsNoTracking().ToList();  

            context.Customers.AddOrUpdate(customers.ToArray());

            for(int i = 0; i < 15; i++)

            {

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

            }           

            context.SaveChanges();

        }

​

        // BulkMerge

        using (var context = new EntityContext())

        {

            var customers = context.Customers.ToList();         

            customers.ForEach(x => x.LastName += "_z");

            for(int i = 0; i < 15; i++)

            {

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

            }

            context.BulkMerge(customers);

        }

        // Clean

        using (var context = new EntityContext())

        {

            context.BulkDelete(context.Customers);

        }

    }

    public static List<Customer> GenerateCustomers(int count)

    {

        var updateCount = count / 2;

        var insertCount = count - updateCount;

        var list = new List<Customer>();

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

        {

            list.Add(new Customer() { Code = "Update_Code_" + i, FirstName = "Update_FirstName_" + i, LastName = "Update_LastName_" + i });

        }

​

        using (var context = new EntityContext())

        {

            context.BulkInsert(list);

        }

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

        {

            list.Add(new Customer() { Code = "Insert_Code_" + i, FirstName = "Insert_FirstName_" + i, LastName = "Insert_LastName_" + i });

        }

        return list;

    }

​

    public class EntityContext : DbContext

    {

        public EntityContext() : base(FiddleHelper.GetConnectionStringSqlServer())

        {

        }

        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; }

    }

    public class BenchmarkResult

    {

        public string Action { get; set; }

        public int Entities { get; set; }

        public string Performance { get; set; }

    }

}