Entity Framework: how to enable cascading deletion in unidirectional objects

Question

There are two objects, for example, below:

public class Business { public int Id {get; set;} public File Logo {get; set;} public int? LogoId {get; set;} public File Video {get; set;} public int? Video {get; set;} public ICollection<File> Images {get; set;} } public class File { // some file props, such as Id, Name, ... } 

How to configure cascading file deletion for deletion? Please note that I do not need navigation from File to Business .

UPDATE:

You can find the modelBuilder configuration as shown below:

  modelBuilder.Conventions.Remove<OneToManyCascadeDeleteConvention>(); modelBuilder.Entity<Entities.Business>() .HasOptional(b => b.Logo) .WithOptionalPrincipal() .WillCascadeOnDelete(); modelBuilder.Entity<Entities.Business>() .HasOptional(b => b.Video) .WithOptionalPrincipal() .WillCascadeOnDelete(); modelBuilder.Entity<Entities.Business>() .HasMany(b => b.Images) .WithOptional() .WillCascadeOnDelete(); 

and here is the error I received:

Representation of the FOREIGN KEY constraint "FK_dbo.Files_dbo.Businesses_Business_Id1" in the Files table can cause loops or multiple cascading paths. Specify ON. REMOVE NO ACTION or ON. UPDATE NO ACTION or change other FOREIGN KEY constraints. Could not create restriction

Answer 1

If you like the individual configuration classes, you can try something like this:

  public class BusinessConfiguration : EntityTypeConfiguration<Business> { public BusinessConfiguration() { HasMany(x => x.Images).WithOptional().WillCascadeOnDelete(); HasOptional(x => x.Logo).WithOptional().WillCascadeOnDelete(); HasOptional(x => x.Video).WithOptional().WillCascadeOnDelete(); } } 

If you don't miss lambda within .WithOptional() or .WithRequired() , then the other side has no navigation properties.