using System;

using System.Collections.Generic;

using System.ComponentModel.DataAnnotations.Schema;

using System.Linq;

using System.Threading.Tasks;

using System.Diagnostics;

using Microsoft.Data.SqlClient;

using Microsoft.EntityFrameworkCore;

using Thinktecture;

public class Program

{

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

    public static async Task Main()

    {

        // Generate X entities

        var customers = GenerateCustomers(1000);

        // Warm up EF

        await JustInTime_Compile(customers);

        using (var context = new EntityContext())

        {

            // Seed

            context.Customers.AddRange(customers);

            await context.SaveChangesAsync();

        }

​

        var customerIds = customers.Select(c => c.CustomerID).ToList();

        var oneCustomer = customerIds.Take(1).ToList();

        var tenCustomers = customerIds.Take(10).ToList();

        var oneHundredCustomers = customerIds.Take(100).ToList();

        var fiveHundredCustomers = customerIds.Take(500).ToList();

        var oneThousandCustomers = customerIds.Take(1000).ToList();

        using (var context = new EntityContext())

        {

            // Read (1)

            var sw = Stopwatch.StartNew();

            var result = await PerformRead(context, oneCustomer);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Read", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Read (10)

            var sw = Stopwatch.StartNew();

            var result = await PerformRead(context, tenCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Read", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Read (100)

            var sw = Stopwatch.StartNew();

            var result = await PerformRead(context, oneHundredCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Read", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Read (500)

            var sw = Stopwatch.StartNew();

            var result = await PerformRead(context, fiveHundredCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Read", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

​

        using (var context = new EntityContext())

        {

            // Read (1000)

            var sw = Stopwatch.StartNew();

            var result = await PerformRead(context, oneThousandCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Read", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Temporary Table (1)

            var sw = Stopwatch.StartNew();

            var result = await PerformTempTableRead(context, oneCustomer);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Temporary Table", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Temporary Table (10)

            var sw = Stopwatch.StartNew();

            var result = await PerformTempTableRead(context, tenCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Temporary Table", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

​

        using (var context = new EntityContext())

        {

            // Temporary Table (100)

            var sw = Stopwatch.StartNew();

            var result = await PerformTempTableRead(context, oneHundredCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Temporary Table", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Temporary Table (500)

            var sw = Stopwatch.StartNew();

            var result = await PerformTempTableRead(context, fiveHundredCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Temporary Table", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Temporary Table (1000)

            var sw = Stopwatch.StartNew();

            var result = await PerformTempTableRead(context, oneThousandCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Temporary Table", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Collection Parameters (1)

            var sw = Stopwatch.StartNew();

            var result = await PerformCollectionParameterRead(context, oneCustomer);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Collection Parameters", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Collection Parameters (10)

            var sw = Stopwatch.StartNew();

            var result = await PerformCollectionParameterRead(context, tenCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Collection Parameters", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Collection Parameters (100)

            var sw = Stopwatch.StartNew();

            var result = await PerformCollectionParameterRead(context, oneHundredCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Collection Parameters", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Collection Parameters (500)

            var sw = Stopwatch.StartNew();

            var result = await PerformCollectionParameterRead(context, fiveHundredCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Collection Parameters", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

        using (var context = new EntityContext())

        {

            // Collection Parameters (1000)

            var sw = Stopwatch.StartNew();

            var result = await PerformCollectionParameterRead(context, oneThousandCustomers);

            sw.Stop();

            BenchmarkResults.Add(new BenchmarkResult()

            {Action = "Collection Parameters", Entities = result.Count, Performance = sw.ElapsedMilliseconds + " ms"});

        }

​

        FiddleHelper.WriteTable(BenchmarkResults);

    }

​

    public static async Task JustInTime_Compile(List<Customer> customers)

    {

        // take maximum 25 customers

        customers = customers.Take(25).ToList();

        var customerIds = customers.Select(c => c.CustomerID).ToList();

        using (var context = new EntityContext())

        {

            // Read

            await PerformRead(context, customerIds);

        }

​

        using (var context = new EntityContext())

        {

            // Temporary Table

            await PerformTempTableRead(context, customerIds);

        }

​

        using (var context = new EntityContext())

        {

            // Collection Parameters

            await PerformCollectionParameterRead(context, customerIds);

        }

    }

    public static async Task<List<Customer>> PerformRead(EntityContext context, List<int> customerIds)

    {

        return await context.Customers.Where(c => customerIds.Contains(c.CustomerID)).ToListAsync();

    }

    public static async Task<List<Customer>> PerformTempTableRead(EntityContext context, List<int> customerIds)

    {

        var tempTableQuery = (await context.BulkInsertValuesIntoTempTableAsync(customerIds)).Query;

        return await context.Customers.Where(c => tempTableQuery.Contains(c.CustomerID)).ToListAsync();

    }

    public static Task<List<Customer>> PerformCollectionParameterRead(EntityContext context, List<int> customerIds)

    {

        var idsQuery = context.CreateScalarCollectionParameter(customerIds);

        return context.Customers.Where(c => idsQuery.Contains(c.CustomerID)).ToListAsync();

    }

​

    public static List<Customer> GenerateCustomers(int count)

    {

        var list = new List<Customer>();

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

        {

            list.Add(new Customer()

            {Name = "Customer_" + i, Description = "Description_" + i, IsActive = i % 2 == 0});

        }

​

        return list;

    }

    public class EntityContext : DbContext

    {

        static EntityContext()

        {

            using (var context = new EntityContext())

            {

                context.Database.EnsureCreated();

            }

        }

​

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

​

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)

        {

            optionsBuilder.UseSqlServer(new SqlConnection(FiddleHelper.GetConnectionStringSqlServer()), providerOptions => providerOptions.AddBulkOperationSupport().AddCollectionParameterSupport());

            base.OnConfiguring(optionsBuilder);

        }

    }

    [Table("Customer")]

    public class Customer

    {

        public int CustomerID { get; set; }

​

        public bool IsActive { get; set; }

​

        public string Description { get; set; }

​

        public string Name { get; set; }

    }

​

    public class BenchmarkResult

    {

        public string Action { get; set; }

​

        public int Entities { get; set; }

​

        public string Performance { get; set; }

    }

}