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Two one-to-many relationships in one table

I have a table with a name SystemAccountthat (until recently) had MasterAccountIDon it that would point to her parent account (obviously int?). My client now told me that sometimes it happens that an account can have two parent accounts (they never had any more). I am trying to tune in a class SystemAccount, but this does not create the relationship that I want.

Here is part of the class code:

[ForeignKey("MasterAccount")]
public int? MasterAccountID { get; set; }

[ForeignKey("SecondMasterAccount")]
public int? SecondMasterAccountID { get; set; }

public virtual SystemAccount MasterAccount { get; set; }

public virtual SystemAccount SecondMasterAccount { get; set; }

public virtual List<SystemAccount> AllSubAccounts { get; set; }

public virtual List<SystemAccount> SecondarySubAccounts { get; set; }

When I do, I get 4 FK in the table, 2 of which are automatically generated ( SystemAccount_IDand SystemAccount_ID1). I even tried putting the attribute [InverseProperty]on MasterAccountand SecondMasterAccountto point to lists, and each time it gives me an error (EDIT: it gives me NullReferenceException).

, " ", , MasterAccount MasterAccountID .

?

EDIT: :

System.NullReferenceException was unhandled by user code
  HResult=-2147467261
  Message=Object reference not set to an instance of an object.
  Source=EntityFramework
  StackTrace:
       at System.Data.Entity.ModelConfiguration.Configuration.Types.EntityTypeConfiguration.Configure(EdmEntityType entityType, EdmModel model)
       at System.Data.Entity.ModelConfiguration.Configuration.ModelConfiguration.ConfigureEntities(EdmModel model)
       at System.Data.Entity.ModelConfiguration.Configuration.ModelConfiguration.Configure(EdmModel model)
       at System.Data.Entity.DbModelBuilder.Build(DbProviderManifest providerManifest, DbProviderInfo providerInfo)
       at System.Data.Entity.DbModelBuilder.Build(DbConnection providerConnection)
       at System.Data.Entity.Infrastructure.EdmxWriter.WriteEdmx(DbContext context, XmlWriter writer)
       at System.Data.Entity.Migrations.Extensions.DbContextExtensions.<>c__DisplayClass1.<GetModel>b__0(XmlWriter w)
       at System.Data.Entity.Migrations.Extensions.DbContextExtensions.GetModel(Action`1 writeXml)
       at System.Data.Entity.Migrations.Extensions.DbContextExtensions.GetModel(DbContext context)
       at System.Data.Entity.Migrations.DbMigrator..ctor(DbMigrationsConfiguration configuration, DbContext usersContext)
       at System.Data.Entity.Migrations.DbMigrator..ctor(DbMigrationsConfiguration configuration)
       at System.Data.Entity.MigrateDatabaseToLatestVersion`2.InitializeDatabase(TContext context)
       at System.Data.Entity.Database.<>c__DisplayClass2`1.<SetInitializerInternal>b__0(DbContext c)
       at System.Data.Entity.Internal.InternalContext.<>c__DisplayClass8.<PerformDatabaseInitialization>b__6()
       at System.Data.Entity.Internal.InternalContext.PerformInitializationAction(Action action)
       at System.Data.Entity.Internal.InternalContext.PerformDatabaseInitialization()
       at System.Data.Entity.Database.Initialize(Boolean force)
       at Tests.Core.UI.SessionStartTests.ShouldSuccessfullyInitializeDatabase() in c:\Projects\Current\tests\Tests.Core\UI\StartTests.cs:line 72
  InnerException:

EDIT 2: :

System.Data.Entity.ModelConfiguration.ModelValidationException : One or more validation errors were detected during model generation:

\tSystem.Data.Entity.Edm.EdmAssociationEnd: : Multiplicity is not valid in Role 'SystemAccount_AllSubAccounts_Target' in relationship 'SystemAccount_AllSubAccounts'. Valid values for multiplicity for the Principal Role are '0..1' or '1'.
\tSystem.Data.Entity.Edm.EdmAssociationEnd: : Multiplicity is not valid in Role 'SystemAccount_AllSubAccounts_Source' in relationship 'SystemAccount_AllSubAccounts'. Because the Dependent Role properties are not the key properties, the upper bound of the multiplicity of the Dependent Role must be '*'.
\tSystem.Data.Entity.Edm.EdmAssociationEnd: : Multiplicity is not valid in Role 'SystemAccount_SecondarySubAccounts_Target' in relationship 'SystemAccount_SecondarySubAccounts'. Valid values for multiplicity for the Principal Role are '0..1' or '1'.
\tSystem.Data.Entity.Edm.EdmAssociationEnd: : Multiplicity is not valid in Role 'SystemAccount_SecondarySubAccounts_Source' in relationship 'SystemAccount_SecondarySubAccounts'. Because the Dependent Role properties are not the key properties, the upper bound of the multiplicity of the Dependent Role must be '*'.

EDIT 3: :

Database.SetInitializer(new MigrateDatabaseToLatestVersion<MyDbContext, Configuration>());
var db = new MyDbContext();
db.Database.Initialize(true);

OnModelCreating:

modelBuilder.Conventions.Remove<OneToManyCascadeDeleteConvention>();

modelBuilder.Entity<ClientStatisticsView>().ToTable("ClientStatistics");

base.OnModelCreating(modelBuilder);

Configuration :

public Configuration()
{
  AutomaticMigrationsEnabled = true;
  AutomaticMigrationDataLossAllowed = true;
}

protected override void Seed(MyDbContext context)
{
}
+3
3

, @Slauma @Moho (+1 !).

, [InverseProperty] , , . , @Moho , . [ForeignKey] , , , ..:

public int? PrimaryParentId { get; set; }
public int? SecondaryParentId { get; set; }

[ForeignKey( "PrimaryParent" )]
public virtual HierarchicalEntity PrimaryParent { get; set; }

[ForeignKey( "SecondaryParent" )]
public virtual HierarchicalEntity SecondaryParent { get; set;}

, . SystemAccount, . , :

  • , FK .
  • . FK .
  • , [InverseProperty] [ForeignKey] virtual.
  • . FK, , - , FKs!

, , ...

+1

InverseProperty?

[InverseProperty( "MasterAccount" )]
public virtual List<SystemAccount> AllSubAccounts { get; set; }

[InverseProperty( "SecondMasterAccount" )]
public virtual List<SystemAccount> SecondarySubAccounts { get; set; }

, :

public class HierarchicalEntity
{
    public int Id { get; set; }
    public string Description { get; set; }

    [ForeignKey( "PrimaryParent" )]
    public int? PrimaryParentId { get; set; }

    [ForeignKey( "SecondaryParent" )]
    public int? SecondaryParentId { get; set; }
    public virtual HierarchicalEntity PrimaryParent { get; set; }

    public virtual HierarchicalEntity SecondaryParent { get; set;}

    [InverseProperty( "PrimaryParent" )]
    public ICollection<HierarchicalEntity> ChildrenViaPrimaryParent { get; set; }

    [InverseProperty( "SecondaryParent" )]
    public ICollection<HierarchicalEntity> ChildrenViaSecondaryParent { get; set; }
}

multiple self-references

+4

EF 5. ​​ , EDIT 2 Moho. EF 6. , EF 6 - , .

If you need to stick to EF 5 using the Fluent API mapping, instead of using the attribute [InverseProperty]that worked for me without exception. You can remove all attributes:

public class SystemAccount
{
    public int ID { get; set; }

    public int? MasterAccountID { get; set; }
    public int? SecondMasterAccountID { get; set; }

    public virtual SystemAccount MasterAccount { get; set; }
    public virtual SystemAccount SecondMasterAccount { get; set; }

    public virtual List<SystemAccount> AllSubAccounts { get; set; }
    public virtual List<SystemAccount> SecondarySubAccounts { get; set; }
}

Relationship mapping with the Fluent API:

modelBuilder.Entity<SystemAccount>()
    .HasOptional(s => s.MasterAccount)
    .WithMany(s => s.AllSubAccounts)
    .HasForeignKey(s => s.MasterAccountID);

modelBuilder.Entity<SystemAccount>()
    .HasOptional(s => s.SecondMasterAccount)
    .WithMany(s => s.SecondarySubAccounts)
    .HasForeignKey(s => s.SecondMasterAccountID);

The fact that an attribute [InverseProperty]with your model throws exceptions seems to be an error in EF 5. The error is most likely related to the self-referencing kind of relationship, because usually the relationship between the various objects that the attribute works without problems.

+3
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