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Domain Modeling and Mapping with EF CPT5

I am trying to simulate an album with a collection of photos. Each album will have a collection of photos and thumb photos. This is what I have, but EF doesn't seem to like it. I am using EF CPT5

Model :

public class Album : IEntity { private DateTime _dateCreated; public Album() { _dateCreated = SystemTime.Now(); Photos = new List<Photo>(); } public long Id { get; set; } public string Name { get; set; } public string Location { get; set; } public DateTime DateCreated { get { return _dateCreated; } set { _dateCreated = value; } } public virtual Site Site { get; set; } public virtual Photo Thumbnail { get; set; } public long ThumbnailId { get; set; } public virtual ICollection<Photo> Photos { get; set; } } public class Photo : IEntity { public Photo() { _dateCreated = SystemTime.Now(); } private DateTime _dateCreated; public long Id { get; set; } public string Caption { get; set; } public string FileName { get; set; } public DateTime DateCreated<br/>{ get { return _dateCreated; } set { _dateCreated = value; } } public long AlbymId { get; set; } public virtual Album Album { get; set; } }

Display Code:

 public class AlbumMap : EntityTypeConfiguration<Album> { public AlbumMap() { HasRequired(x => x.Thumbnail).WithMany().HasForeignKey(a => a.ThumbnailId).WillCascadeOnDelete(false); Property(x => x.Location).IsVariableLength().HasMaxLength(80); Property(x => x.Name).IsVariableLength().HasMaxLength(80).IsRequired(); } } public class PhotoMap : EntityTypeConfiguration<Photo> { public PhotoMap() { HasRequired(p => p.Album).WithMany(a => a.Photos).HasForeignKey(p => p.AlbymId); Property(x => x.FileName).IsVariableLength().HasMaxLength(255).IsRequired(); Property(x => x.Caption).IsVariableLength().HasMaxLength(255); Property(x => x.DateCreated); ToTable("SiteAlbumPhotos"); } }

Context

 public class Database : ObjectContext { public Database(EntityConnection connection) : base(connection) { ContextOptions.LazyLoadingEnabled = true; ContextOptions.ProxyCreationEnabled = true; } private IObjectSet<User> _users; private IObjectSet<Site> _sites; private IObjectSet<SiteDonation> _donations; private IObjectSet<SiteAnnouncement> _siteAnnouncements; private IObjectSet<SiteData> _siteData; private IObjectSet<SiteLink> _siteLinks; private IObjectSet<SitePost> _sitePosts; private IObjectSet<Theme> _theme; private IObjectSet<Album> _siteAlbums; private IObjectSet<Photo> _siteAlbumPhotos; private IObjectSet<CommunityPost> _communityPosts; private IObjectSet<CommunityComment> _communityComments; public IObjectSet<User> Users { get{ return _users ?? (_users = ObjectSet<User>()); } } public IObjectSet<Album> SiteAlbums { get { return _siteAlbums ?? (_siteAlbums = ObjectSet<Album>()); } } public IObjectSet<Photo> SiteAlbumsPhotos { get { return _siteAlbumPhotos ?? (_siteAlbumPhotos = ObjectSet<Photo>()); } } public IObjectSet<Site> Sites { get{ return _sites ?? (_sites = ObjectSet<Site>()); } } public IObjectSet<SiteDonation> SiteDonations { get { return _donations ?? (_donations = ObjectSet<SiteDonation>()); } } public IObjectSet<SiteAnnouncement> SiteAnnouncements { get { return _siteAnnouncements ?? (_siteAnnouncements = ObjectSet<SiteAnnouncement>()); } } public IObjectSet<SiteData> SiteData { get { return _siteData ?? (_siteData = ObjectSet<SiteData>()); } } public IObjectSet<SiteLink> SiteLinks { get { return _siteLinks ?? (_siteLinks = ObjectSet<SiteLink>()); } } public IObjectSet<SitePost> SitePosts { get { return _sitePosts ?? (_sitePosts = ObjectSet<SitePost>()); } } public IObjectSet<Theme> Themes { get { return _theme ?? (_theme = ObjectSet<Theme>()); } } public IObjectSet<CommunityPost> CommunityPosts { get { return _communityPosts ?? (_communityPosts = ObjectSet<CommunityPost>()); } } public IObjectSet<CommunityComment> CommunityComments { get { return _communityComments ?? (_communityComments = ObjectSet<CommunityComment>()); } } public virtual IObjectSet<T> ObjectSet<T>() where T : class, IEntity { return CreateObjectSet<T>(); } public virtual void Commit() { SaveChanges(); } }

DatabaseFactory

 public class DatabaseFactory : Disposable, IDatabaseFactory { private static readonly ModelBuilder builder = CreateBuilder(); private readonly DbProviderFactory _providerFactory; private readonly string _connectionString; private Database _database; // public DatabaseFactory(DbProviderFactory providerFactory, string connectionString) { Check.Argument.IsNotNull(providerFactory, "providerFactory"); Check.Argument.IsNotNullOrEmpty(connectionString, "connectionString"); _providerFactory = providerFactory; _connectionString = connectionString; } // public Database Get() { if(_database == null) { var connection = _providerFactory.CreateConnection(); connection.ConnectionString = _connectionString; //_database = builder.CreateModel(connection); LEG 1 CPT 3 //var ctx = dbModel.CreateObjectContext<ObjectContext>(_connectionString); LEG 1 CPT 3 //var modelBuilder = builder.CreateModel(); LEG 2 CPT 4 //_database = modelBuilder.CreateObjectContext<Database>(connection); LEG 2 CPT 4 //_database = modelBuilder.CreateObjectContext<Database>(connection); LEG 2 CPT 4 var modelBuilder = builder.Build(connection); var dbModel = new DbModel(modelBuilder); _database = dbModel.CreateObjectContext<Database>(connection); } return _database; } // protected override void DisposeCore() { if (_database != null) { _database.Dispose(); } } // private static ModelBuilder CreateBuilder() { //ContextBuilder<Database> contextBuilder = new ContextBuilder<Database>(); var contextBuilder = new ModelBuilder(); //IEnumerable<Type> configurationTypes = typeof(DatabaseFactory) // .Assembly // .GetTypes() // .Where(type => type.IsPublic && type.IsClass && !type.IsAbstract && !type.IsGenericType && typeof(StructuralTypeConfiguration).IsAssignableFrom(type) && (type.GetConstructor(Type.EmptyTypes) != null)); //foreach (StructuralTypeConfiguration configuration in configurationTypes.Select(type => (StructuralTypeConfiguration)Activator.CreateInstance(type))) //{ // contextBuilder.Configurations.Add(configuration); //} contextBuilder.Configurations.Add(new CommunityCommentMap()); contextBuilder.Configurations.Add(new CommunityPostMap()); contextBuilder.Configurations.Add(new SiteAlbumMap()); contextBuilder.Configurations.Add(new SiteAlbumPhotoMap()); contextBuilder.Configurations.Add(new SiteAnnouncementMap()); contextBuilder.Configurations.Add(new SiteDataMap()); contextBuilder.Configurations.Add(new SiteDonationMap()); contextBuilder.Configurations.Add(new SiteLinkMap()); contextBuilder.Configurations.Add(new SiteMap()); contextBuilder.Configurations.Add(new SitePostMap()); contextBuilder.Configurations.Add(new ThemeMap()); contextBuilder.Configurations.Add(new UserMap()); return contextBuilder; } }

Am I correct modeling and matching? I need to create a new album without specifying a thumbnail. At the moment, everything works until I try to add a thumbnail, after which I get this error:

System.Data.UpdateException: Unable to determine the actual ordering for dependent operations. Dependencies may exist due to foreign key restrictions, model requirements, or store values.

in System.Data.Mapping.Update.Internal.UpdateTranslator.DependencyOrderingError (remainder IEnumerable`1) in System.Data.Mapping.Update.Internal.UpdateTranslator.ProduceCommands () in System.Data.Mapping.Update.Internal.Updatedranslator (IEntityStateManager stateManager, IEntityAdapter adapter) in System.Data.Objects.ObjectContext.SaveChanges (SaveOptions options) in PostHope.Infrastructure.DataAccess.Database.Commit () in Database.cs: line 74 in PostHope.Infrastructure.DataAccess.IntegrationTests.BuDild .Add_test_data_to_database () in BuildDatabase.cs: line 252

Any help would be great!

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We reviewed this question EF CTP4 here . Now here is the update for EF CTP5, which was previously released earlier.

 public class Photo { public long PhotoId { get; set; } [MaxLength(255)] public string Caption { get; set; } [MaxLength(255)][Required] public string FileName { get; set; } public DateTime DateCreated { get; set; } public long AlbumId { get; set; } public virtual Album Album { get; set; } } [Table("SiteAlbumPhotos")] public class Album { public long AlbumId { get; set; } [MaxLength(80)][Required] public string Name { get; set; } [MaxLength(80)] public string Location { get; set; } public DateTime DateCreated { get; set; } public long ThumbnailId { get; set; } public virtual Photo Thumbnail { get; set; } public virtual ICollection<Photo> Photos { get; set; } } public class PhotoMap : EntityTypeConfiguration<Photo> { public PhotoMap() { HasRequired(p => p.Album).WithMany(a => a.Photos) .HasForeignKey(p => p.AlbumId); } } public class AlbumMap : EntityTypeConfiguration<Album> { public AlbumMap() { HasRequired(a => a.Thumbnail).WithMany() .HasForeignKey(a => a.ThumbnailId) .WillCascadeOnDelete(false); } } public class MyContext : DbContext { public DbSet<Photo> Photos { get; set; } public DbSet<Album> Albums { get; set; } protected override void OnModelCreating(ModelBuilder modelBuilder) { modelBuilder.Configurations.Add<Photo>(new PhotoMap()); modelBuilder.Configurations.Add<Album>(new AlbumMap()); } }

What are the results of this DB schema: alt text

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