static void Main(string[] args)
{
using (var db = new Northwind())
{
using (IDbContextTransaction t =
db.Database.BeginTransaction())
{
WriteLine($"Transaction started with this isolation level: { t.GetDbTransaction().IsolationLevel}");
//var loggerFactory = db.GetService<ILoggerFactory>();
//loggerFactory.AddProvider(new ConsoleLogProvider());
WriteLine("List of categories and the number of products:");
IQueryable <Category> cats;
//db.Categories;//.Include(c => c.Products);
Write("Enable eager loading? (Y/N): ");
bool eagerloading = (ReadKey().Key == ConsoleKey.Y);
bool explicitloading = false;
WriteLine();
if (eagerloading)
{
cats = db.Categories.Include(c => c.Products);
}
else
{
cats = db.Categories;
Write("Enable explicit loading? (Y/N): ");
explicitloading = (ReadKey().Key == ConsoleKey.Y);
WriteLine();
}
foreach (Category c in cats)
{
if (explicitloading)
{
Write($"Explicitly load products for {c.CategoryName}? (Y/N): ");
if (ReadKey().Key == ConsoleKey.Y)
{
var products = db.Entry(c).Collection(c2 => c2.Products);
if (!products.IsLoaded)
{
products.Load();
}
}
WriteLine();
}
WriteLine(
$"{c.CategoryName} has {c.Products.Count} products.");
}
WriteLine("List of products that cost more than a given price with most expensive first.");
string input;
decimal price;
do
{
Write("Enter a product price: ");
input = ReadLine();
} while (!decimal.TryParse(input, out price));
IQueryable <Product> prods = db.Products
.Where(product => product.UnitPrice > price)
.OrderByDescending(product => product.UnitPrice);
foreach (Product item in prods)
{
WriteLine($"{item.ProductID}: {item.ProductName} costs {item.UnitPrice:$#,##0.00}");
}
var newProduct = new Product
{
CategoryID = 6, // Meat & Poultry
ProductName = "Bob's Burger",
UnitPrice = 500M
};
// 새 product를 추가한다.
db.Products.Add(newProduct);
// 변경 사항을 데이터베이스에 저장한다.
db.SaveChanges();
foreach (var item in db.Products)
{
WriteLine($"{item.ProductID}: {item.ProductName} costs {item.UnitPrice:$#,##0.00}");
}
Product updateProduct = db.Products.First(
p => p.ProductName.StartsWith("Bob"));
updateProduct.UnitPrice += 20M;
db.SaveChanges();
foreach (var item in db.Products)
{
WriteLine($"{item.ProductID}: {item.ProductName} costs {item.UnitPrice:$#,##0.00}");
}
Product deleteProduct = db.Products.First(p => p.ProductName.StartsWith("Bob"));
db.Products.Remove(deleteProduct);
db.SaveChanges();
foreach (var item in db.Products)
{
WriteLine($"{item.ProductID}: {item.ProductName} costs {item.UnitPrice:$#,##0.00}");
}
t.Commit();
}
}
}
static void Main(string[] args)
{
//Console.WriteLine("Hello World!");
using (var db = new Northwind())
{
// 트랜젝션 처리
using (IDbContextTransaction t = db.Database.BeginTransaction())
{
WriteLine($"Transaction started with this isolation level: {t.GetDbTransaction().IsolationLevel}");
// 로그처리
//var loggerFactory = db.GetService<ILoggerFactory>();
//loggerFactory.AddProvider(new ConsoleLogProvider());
WriteLine("List of categories and the number of products:");
IQueryable <Category> cats =
db.Categories.Include(c => c.Products);
foreach (Category c in cats)
{
WriteLine($"{c.CategoryName} has {c.Products.Count} products.");
}
WriteLine("List of products that cost more than a given price with most expensive first.");
string input;
decimal price;
do
{
Write("Enter a product price:");
input = ReadLine();
}while(!decimal.TryParse(input, out price));
IQueryable <Product> prods = db.Products
.Where(product => product.UnitPrice > price)
.OrderByDescending(product => product.UnitPrice);
foreach (Product item in prods)
{
WriteLine($"{item.ProductID}: {item.ProductName} costs {item.UnitPrice:$#,##0.00}");
}
/*
* var newProduct = new Product{
* CategoryID = 6,
* ProductName = "Bob's burger",
* UnitPrice = 500M
* };
*
* // 새 product를 추가한다.
* db.Products.Add(newProduct);
*
* // 변경사항을 데이터베이스에 저장한다.
* db.SaveChanges();
*
* //foreach(var item in db.Products)
* //{
* // WriteLine($"{item.ProductID}: {item.ProductName} costs {item.UnitPrice:$#,##0.00}");
* //}
*
*
* /*
* // 엔티티 업데이트
* Product updateProduct = db.Products.First(
* p => p.ProductName.StartsWith("Bob")
* );
* updateProduct.UnitPrice += 20M;
* db.SaveChanges();
* foreach(var item in db.Products)
* {
* WriteLine($"{item.ProductID}: {item.ProductName} costs {item.UnitPrice:$#,##0.00}");
* }
*/
/*
* // 엔티티 삭제
* Product deleteProduct = db.Products.First(
* p => p.ProductName.StartsWith("Bob")
* );
* db.Products.Remove(deleteProduct);
* db.SaveChanges();
* foreach(var item in db.Products)
* {
* WriteLine($"{item.ProductID}: {item.ProductName} costs {item.UnitPrice:$#,##0.00}");
* }
* //*/
foreach (var item in db.Products)
{
WriteLine($"{item.ProductID}: {item.ProductName} costs {item.UnitPrice:$#,##0.00}");
}
t.Commit();
}
}
}