public static void Slow()
{
var db = new globalfactory2021Context();
var productName = "DummyP";
for (int i = 0; i < 1000; i++)
{
var product = new Product
{
Name = productName,
Price = 11,
Manufacturerid = 2
};
db.Products.Add(product);
}
var toRemoves = db.Products.Where(p => p.Name == productName).ToList();
foreach (var toRemove in toRemoves)
{
db.Products.Remove(toRemove);
}
db.Dispose();
}
public static void Fast()
{
var db = new globalfactory2021Context();
var productName = "DummyP";
var toAdd = new List <Product>();
for (int i = 0; i < 1000; i++)
{
var product = new Product
{
Name = productName,
Price = 11,
Manufacturerid = 2
};
toAdd.Add(product);
}
db.Products.AddRange(toAdd);
var toRemoves = db.Products.Where(p => p.Name == productName).ToList();
db.Products.RemoveRange(toRemoves);
db.Dispose();
}
private static void SeedData(globalfactory2021Context db)
{
var manufacturer = new Manufacturer
{
Country = "Test country",
Name = ManufacturerName
};
var products = new List <Product>();
var random = new Random();
for (var i = 0; i < 10000; i++)
{
var product = new Product
{
Name = (i % 2 == 0) ? TestProduct1Name : TestProduct2NameNotPadded.PadRight(13),
Manufacturer = manufacturer,
Price = (decimal)random.NextDouble() * MaxPrice
};
products.Add(product);
}
manufacturer.Products = products;
db.Manufacturers.Add(manufacturer);
db.SaveChanges();
db.Dispose();
}
public static void Default()
{
var db = new globalfactory2021Context();
var product = db.Products
.ToList();
db.Dispose();
}
/// <summary>
/// Key difference: equals
/// </summary>
public static void Slow()
{
var db = new globalfactory2021Context();
var filtered = db.Products
.Where(p => p.Name.Equals(DataSeeding.TestProduct1Name))
.ToList();
db.Dispose();
}
public static void Lazy()
{
var db = new globalfactory2021Context();
var product = db.Products.First();
// Lazy loaded
var manufacturer = product.Manufacturer;
db.Dispose();
}
/// <summary>
/// Key difference: format multiple times
/// </summary>
public static void Slow()
{
var db = new globalfactory2021Context();
var filtered = db.Products
.Where(p => p.Name.Trim() == DataSeeding.TestProduct2NameNotPadded)
.ToList();
db.Dispose();
}
public static void AsNoTracking()
{
var db = new globalfactory2021Context();
var product = db.Products
.AsNoTracking()
.ToList();
db.Dispose();
}
/// <summary>
/// Key difference: IEnumerable
/// </summary>
public static void Slow()
{
var db = new globalfactory2021Context();
IEnumerable <Product> products = db.Products;
var filtered = products
.Where(p => p.Name == DataSeeding.TestProduct1Name)
.ToList();
db.Dispose();
}
/// <summary>
/// Key difference: ==
/// </summary>
public static void Fast()
{
var db = new globalfactory2021Context();
// Some expressions were meant for direct C#-To-SQL translation.
// Others, like .equals, were not.
var filtered = db.Products
.Where(p => p.Name == DataSeeding.TestProduct1Name)
.ToList();
db.Dispose();
}
public static void Eager()
{
var db = new globalfactory2021Context();
var manufacturer = db.Products
// Eager loaded
.Include(p => p.Manufacturer)
.First()
.Manufacturer;
db.Dispose();
}
/// <summary>
/// Key difference: IQueryable
/// </summary>
public static void Fast()
{
var db = new globalfactory2021Context();
// IQueryable is a data structure still able to translate a C# expression to a SQL query.
// SQL is much faster for lookups than C#.
// 10 times faster.
IQueryable <Product> products = db.Products;
var filtered = products
.Where(p => p.Name == DataSeeding.TestProduct1Name)
.ToList();
db.Dispose();
}
/// <summary>
/// Key difference: format once
/// </summary>
public static void Fast()
{
var db = new globalfactory2021Context();
// When using char or nchar- you will have a padded field
// In order to find it, you will need to to make both sides:
// filter and the column- to be of the same format
// instead of trimming every column (n)
// format the filter to match the formatting of a column (1)
var filter = DataSeeding.TestProduct2NameNotPadded.PadLeft(13);
var filtered = db.Products
.Where(p => p.Name == filter)
.ToList();
db.Dispose();
}