EF基础二，EF5，NET4.5，ANNOTATION AND FLUENT API,MOST FOCUS ON ENTITYTYPECONFIGURATION.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data.Entity;
using System.ComponentModel.DataAnnotations.Schema;
using System.Data.Entity.ModelConfiguration;

namespace BlueSea
{
    class Program
    {
        static void Main(string[] args)
        {
            Database.SetInitializer(new DropCreateDatabaseIfModelChanges<BlueSeaContext>());
            InsertDestination();
            InsertTrip();
            UpdateTrip();
            InsertPserson();
            UpdatePerson();
        }
        private static void InsertDestination()
        {
            var destination = new Destination
            {
                Country = "Indonesia",
                Description = "Tourism in Bali",
                Name = "Bali"
            };
            using (var context = new BlueSeaContext())
            {
                context.Destinations.Add(destination);
                context.SaveChanges();
            }
        }
        private static void InsertTrip()
        {
            var trip = new Trip
            {
                CostUSD = 800,
                StatrtDate = new DateTime(2013, 3, 15),
                EndDate = new DateTime(2013, 3, 20)
            };
            using (var context = new BlueSeaContext())
            {
                context.Trips.Add(trip);
                context.SaveChanges();
            }
        }
        private static void UpdateTrip()
        {
            using (var cntext = new BlueSeaContext())
            {
                var trip = cntext.Trips.FirstOrDefault();
                trip.CostUSD = 750;
                cntext.SaveChanges();
            }
        }  
        private static void InsertPserson()
        {
            var person = new Person
            {
                FirstName = "Martin",
                LastName = "Jack",
                SocialSecurityNumber = 12345678
            };
            using (var context = new BlueSeaContext())
            {
                context.People.Add(person);
                context.SaveChanges();
            }
        }
        private static void UpdatePerson()
        {
            using (var context = new BlueSeaContext())
            {
                var person = context.People.FirstOrDefault();
                person.FirstName = "Peter";
                context.SaveChanges();
            }
        }
    }
    public class Destination
    {
        public int DestinatonID { get; set; }
        public string Name { get; set; }
        public string Country { get; set; }
        public string Description { get; set; }
        public byte[] Photo { get; set; }

        public virtual ICollection<Lodging> Lodgings { get; set; }
    }
    public class DestinationConfiguration : EntityTypeConfiguration<Destination>
    {
        public DestinationConfiguration()
        {
            HasKey(d => d.DestinatonID);
            Property(d => d.Name).IsRequired();
            Property(d => d.Description).HasMaxLength(500);
            Property(d => d.Photo).HasColumnType("image");
        }
    }
    public class Lodging
    {
        public int LodgingID { get; set; }
        public string Name { get; set; }
        public string Owener { get; set; }
        public bool IsResort { get; set; }
        public decimal MileFromAirport { get; set; }

        public virtual Destination Destination { get; set; }
    }
    public class LodgingConfiguration : EntityTypeConfiguration<Lodging>
    {
        public LodgingConfiguration()
        {
            Property(l => l.Name).IsRequired().HasMaxLength(200);
            Property(l => l.MileFromAirport).HasPrecision(8, 1);
            Property(l => l.Owener).IsUnicode(fals