private static void InsertCarsintoSQL_UsingEntityFramework(List <Car> cars, List <Manufacturer> manufacturers)
{
Database.SetInitializer(new DropCreateDatabaseIfModelChanges <CarDB>());
var db = new CarDB();
//db.Database.Log = Console.WriteLine;
if (!db.cars.Any())
{
foreach (var car in cars)
{
db.cars.Add(car);
}
db.SaveChanges();
}
Console.WriteLine("Cars DB created and cars are populated");
var db_M = new ManufacturersDB();
if (!db_M.Manufacturers.Any())
{
foreach (var manufacturer in manufacturers)
{
db_M.Manufacturers.Add(manufacturer);
}
db_M.SaveChanges();
}
Console.WriteLine("Manufacturers DB created and Manufacturers are populated");
Console.ReadLine();
}
private static void InsertData()
{
var cars = ProcessCars("fuel.csv");
var db = new CarDB();
db.Database.Log = Console.WriteLine;
if (!db.Cars.Any())
{
foreach (var car in cars)
{
db.Cars.Add(car);
}
}
db.SaveChanges();
}
private static void QueryingFromDB_UsingEF()
{
var db = new CarDB();
db.Database.Log = Console.WriteLine;
//var query = from car in db.cars
// orderby car.FE_Comb descending, car.Carline ascending
// select car;
var query2 = db.cars.OrderByDescending(c => c.FE_Comb)
.ThenBy(c => c.Carline)
.ToList()
.Take(10);
foreach (var car in query2)
{
Console.WriteLine($"{car.Carline} : {car.FE_Comb}");
}
}
private static void QueryData()
{
var db = new CarDB();
db.Database.Log = Console.WriteLine;
var query =
//1st
//from car in db.Cars
//orderby car.Combined descending, car.Name ascending
//select car;
//2nd
//db.Cars.Where(c => c.Manufacturer == "BMW")
//.OrderByDescending(c => c.Combined)
//.ThenBy(c => c.Name)
//.Take(10)
//.Select(c => new { Name = c.Name.Split(' '});
//once u select .ToList() it becomes concrete data, not deferred execution
//3rd
//db.Cars.GroupBy(c => c.Manufacturer)
// .Select(g => new
// {
// Name = g.Key,
// Cars = g.OrderByDescending(c => c.Combined).Take(2)
// });
//4th
from car in db.Cars
group car by car.Manufacturer into manufacturer
select new
{
Name = manufacturer.Key,
Cars = (from car in manufacturer
orderby car.Combined descending
select car).Take(2)
};
//1st
//foreach (var car in query.Take(10))
//{
// Console.WriteLine($"{car.Name} : {car.Combined}");
//}
//2nd
//foreach (var item in query)
//{
// Console.WriteLine(item.Name);
//}
//3rd
foreach (var group in query)
{
Console.WriteLine(group.Name);
foreach (var car in group.Cars)
{
Console.WriteLine($"\t{car.Name} : {car.Combined}");
}
}
}
