using System;

using System.Linq;

using System.Data.Entity;

using System.Collections;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        using (var ctx = new DatabaseContext())

        {

            InitializeDB(ctx);

            //Ejemplo de impresion

            foreach (var purchase in ctx.Purchases)

            {

                Console.WriteLine(purchase.PurchaseId.ToString());

            }

        }

    }

    public static void InitializeDB(DatabaseContext ctx){

        ctx.Customers.Add(new Customer(){CustomerId = 1, FullName = "Sanchez Mario", DateOfBirth = new DateTime(1985,10,18)});

        ctx.Customers.Add(new Customer(){CustomerId = 2, FullName = "Gimenez Pedro", DateOfBirth = new DateTime(2010,01,10)});

        ctx.Customers.Add(new Customer(){CustomerId = 3, FullName = "Gomez Ricardo", DateOfBirth = new DateTime(1993,11,25)});

        ctx.Customers.Add(new Customer(){CustomerId = 4, FullName = "Araujo María", DateOfBirth = new DateTime(2009,12,2)});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1001, PurchaseDateUTC = new DateTime(2021,2,2,15,22,35), Total = 255m, CustomerId = 1});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1002, PurchaseDateUTC = new DateTime(2021,2,7,12,07,45), Total = 888m, CustomerId = 3});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1003, PurchaseDateUTC = new DateTime(2021,2,9,9,00,10), Total = 672m, CustomerId = 1});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1004, PurchaseDateUTC = new DateTime(2021,1,2,10,12,32), Total = 1000m, CustomerId = 1});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1005, PurchaseDateUTC = new DateTime(2021,1,4,2,25,55), Total = 56m, CustomerId = 2});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1006, PurchaseDateUTC = new DateTime(2021,1,7,3,12,57), Total = 75m, CustomerId = 2});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1007, PurchaseDateUTC = new DateTime(2021,1,12,1,17,12), Total = 987m, CustomerId = 3});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1008, PurchaseDateUTC = new DateTime(2021,1,15,8,55,00), Total = 12000m, CustomerId = 3});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1009, PurchaseDateUTC = new DateTime(2021,1,25,10,43,10), Total = 1m, CustomerId = 3});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1010, PurchaseDateUTC = new DateTime(2021,2,2,17,32,22), Total = 100m, CustomerId = 4});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1011, PurchaseDateUTC = new DateTime(2021,2,2,15,22,35), Total = 256m, CustomerId = 1});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1012, PurchaseDateUTC = new DateTime(2021,2,7,12,07,45), Total = 887m, CustomerId = 3});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1013, PurchaseDateUTC = new DateTime(2021,2,9,9,00,10), Total = 673m, CustomerId = 1});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1014, PurchaseDateUTC = new DateTime(2021,1,12,1,17,12), Total = 987m, CustomerId = 3});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1015, PurchaseDateUTC = new DateTime(2021,1,15,8,55,00), Total = 12000m, CustomerId = 3});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1016, PurchaseDateUTC = new DateTime(2021,1,25,10,43,10), Total = 1m, CustomerId = 3});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1017, PurchaseDateUTC = new DateTime(2021,1,25,12,43,10), Total = 111m, CustomerId = 3});

        ctx.Purchases.Add(new Purchase(){PurchaseId = 1018, PurchaseDateUTC = new DateTime(2021,1,25,16,43,10), Total = 10m, CustomerId = 3});

        ctx.SaveChanges(); 

    }

}

​

public class Purchase

{

    public int PurchaseId {get; set;}

    public DateTime PurchaseDateUTC { get;set;}

    public Decimal Total { get;set; }

    public int CustomerId {get; set;}

    public virtual Customer Customer {get;set;}

}

​

public class Customer

{

    public int CustomerId {get; set;}

    public string FullName {get; set;}

    public DateTime DateOfBirth {get;set;}

}

​

public class DatabaseContext: DbContext 

{

    public DatabaseContext() : base(FiddleHelper.GetConnectionStringSqlServer()) 

    {

    }

    public DbSet<Purchase> Purchases { get; set; }

    public DbSet<Customer> Customers { get; set; }

}

​