Benchmark.cs

using BenchmarkDotNet.Attributes;
using Microsoft.EntityFrameworkCore;

namespace FirstSingle;

[SimpleJob]
public class BenchmarkDb
{
    private readonly TestDbContext _db;
    private readonly int _orderId;

    public BenchmarkDb()
    {
        _db = new TestDbContext();
        var rnd = new Random();
        _orderId  = rnd.Next(1, 1_000_000);
    }

    [Benchmark]
    public async Task Single() => await _db.Orders.SingleAsync(x => x.OrderId == _orderId);
    
    [Benchmark]
    public async Task First() => await _db.Orders.FirstAsync(x => x.OrderId == _orderId);

}