static void Main(string[] args) { // add connection string // add entity fw CarDatabaseEntities db = new CarDatabaseEntities(); Console.WriteLine(db.CAR.Count()); //var q = from car in db.CAR // group car by car.BRAND into grp // select new // { // Brand = grp.Key.brand_name, // AvgPrice = grp.Average(car => car.car_baseprice) // }; //foreach (var item in q) Console.WriteLine(item); // ---- CarLogic cl = new CarLogic(); Console.WriteLine("----"); foreach (var item in cl.GetBrandAverages()) { Console.WriteLine(item); } Console.WriteLine("----"); foreach (var item in cl.GetCarsWithLetter('a', false)) { Console.WriteLine(item); } cl.InsertCar(new CAR() { car_model = "Ford mustang", car_baseprice = 990, car_discountprice = 10, car_brand = 1, car_id = 5 // no identity ~ auto incr. }); cl.DeleteCar(1); Console.WriteLine("----"); foreach (var item in cl.GetAll()) { Console.WriteLine($"{item.car_model} {item.car_baseprice} {item.car_discountprice}"); } Console.WriteLine("----"); Console.WriteLine(cl.GetCheapestCarModel()); }