// Entity Framework Extensions

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

​

// @nuget: Microsoft.EntityFrameworkCore.SqlServer

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

​

using System.Diagnostics;

using System.Linq;

using Microsoft.EntityFrameworkCore;

using System.Collections.Generic;

using Microsoft.Data.SqlClient;

​

public class Program

{

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

    public static void Main()

    {

        using (var context = new EntityContext())

        {

            context.Database.EnsureCreated();

        }

        JustInTime_Compile();

        // Generate X customers

        int customerCount = 1000;

​

        var clockSaveChanges = new Stopwatch();

        var clockBulkDelete = new Stopwatch();

        using (var context = new EntityContext())

        {

            GenerateCustomers(customerCount);           

            context.Customers.RemoveRange(context.Customers);

​

            clockSaveChanges.Start();

            // SaveChanges

            context.SaveChanges();

            clockSaveChanges.Stop();

​

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

        }

        using (var context = new EntityContext())

        {

            GenerateCustomers(customerCount);

​

            var customers = context.Customers.ToList();         

​

            clockBulkDelete.Start();

            // BulkDelete

            context.BulkDelete(customers);

            clockBulkDelete.Stop();

​

            BenchmarkResults.Add(new BenchmarkResult() { Action = "BulkDelete (EF Extensions)", Entities = customerCount, Performance = clockBulkDelete.ElapsedMilliseconds + " ms" });

        }

        FiddleHelper.WriteTable(BenchmarkResults);

    }

    public static void JustInTime_Compile()

    {

        // SaveChanges

        using (var context = new EntityContext())

        {

            GenerateCustomers(10);      

            context.Customers.RemoveRange(context.Customers);

            context.SaveChanges();

        }

​

        // BulkDelete

        using (var context = new EntityContext())

        {

            GenerateCustomers(10);  

​

            context.BulkDelete(context.Customers);

        }

    }

    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, options => options.AutoMapOutputDirection = false);

        }

        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; }

    }

    public class BenchmarkResult

    {

        public string Action { get; set; }

        public int Entities { get; set; }

        public string Performance { get; set; }

    }

}