private static async Task <List <Order>?> LoadOrders(string connectionString, StreamWriter?file) { var builder = new DbContextOptionsBuilder <BotDbContext>(); builder.UseNpgsql(connectionString); var sqlCtx = new BotDbContext(builder.Options); var timer = Stopwatch.StartNew(); //var ordersCount = 100; var ordersCount = 1_000_000; var orders = await sqlCtx.QueryOrders().OrderByDescending(x => x.DateTime).Take(ordersCount).ToListAsync(); file.WriteLine($"Loaded {orders.Count} orders ({timer.ElapsedMilliseconds} ms)"); var minTime = orders.MinF(x => x.DateTime); var maxTime = orders.MaxF(x => x.DateTime); file.WriteLine($"Orders time approximately {minTime} - {maxTime}"); return(orders); }