I have following model and database created using Entity Framework. Is it proper TPT Inheritance?
Is it possible to make the base class as abstract?
Model
Database
CODE
namespace LijosEF
{
public partial class Book
{
public override void Sell()
{
this.AvailabilityStatus = "BookSOLD";
}
}
public partial class DigitalDisc
{
public override void Sell()
{
this.AvailabilityStatus = "DiscSOLD";
}
}
public partial class SellingItem
{
public virtual void Sell()
{
//Do nothing
}
}
}
Client
namespace LijosEF
{
class Program
{
static string connectionStringVal;
static void Main(string[] args)
{
SqlConnectionStringBuilder sqlBuilder = new SqlConnectionStringBuilder();
sqlBuilder.DataSource = ".";
sqlBuilder.InitialCatalog = "LibraryReservationSystem";
sqlBuilder.IntegratedSecurity = true;
// Initialize the EntityConnectionStringBuilder.
EntityConnectionStringBuilder entityBuilder = new EntityConnectionStringBuilder();
entityBuilder.Provider = "System.Data.SqlClient";
entityBuilder.ProviderConnectionString = sqlBuilder.ToString();
entityBuilder.Metadata = @"res://*/MyModelFirstTest.csdl|res://*/MyModelFirstTest.ssdl|res://*/MyModelFirstTest.msl";
connectionStringVal = entityBuilder.ToString();
//AddBook();
//AddDisc();
//MakePurchase();
int billAmount = GetTotalPurchaseValue(1);
}
private static void AddBook()
{
using (var db = new MyModelFirstTestContainer(connectionStringVal))
{
Book book = new Book();
book.AvailabilityStatus = "Available";
book.Price = 150;
book.Title = "Maths Easy";
db.SellingItems.AddObject(book);
db.SaveChanges();
}
}
private static void MakePurchase()
{
using (var db = new MyModelFirstTestContainer(connectionStringVal))
{
DigitalDisc disc = db.SellingItems.OfType<DigitalDisc>().FirstOrDefault(p => p.Artist == "Turtle Violin");
disc.Sell(); //Changes State
Book book = db.SellingItems.OfType<Book>().FirstOrDefault(p => p.Title == "Maths Easy");
book.Sell(); //Changes State
Purchase purchase = new Purchase();
purchase.Date = DateTime.Now;
purchase.SellingItems.Add(book);
purchase.SellingItems.Add(disc);
db.Purchases.AddObject(purchase);
db.SaveChanges();
}
}
private static int GetTotalPurchaseValue(int purchaseID)
{
using (var db = new MyModelFirstTestContainer(connectionStringVal))
{
var purchase = db.Purchases.FirstOrDefault(p => p.PurchaseId == purchaseID);
if( purchase == null)
{
return 0;
}
var total = purchase.SellingItems.Sum(x => Convert.ToInt32(x.Price));
return total;
}
}
private static void AddDisc()
{
using (var db = new MyModelFirstTestContainer(connectionStringVal))
{
DigitalDisc disc = new DigitalDisc();
disc.AvailabilityStatus = "Available";
disc.Price = 300;
disc.Artist = "Turtle Violin";
db.SellingItems.AddObject(disc);
db.SaveChanges();
}
}
}
}
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