How to Access Parent Entity

[wlandgraf (Wagner Landgraf)]

@Silber_Felix

How can I access the Parent Entity, without adding a Field to the Child-Entity?

You can't. You have to have the child entity.

@Silber_Felix

I tried to add FParentId to TChild, but this raises an error, because UpdateDatabase then tries to add 2 Columns parent_id...

This is because you have to tell Aurelius that one side of the association refers to the other side of the association. You do this by using the MappedBy parameter of the ManyValuedAssociation attribute.

This is explained in the ManyValuedAssociation documentation, more specifically this code snipped:

Example using MappedBy parameter:

TMediaFile = class
private
  [Association([TAssociationProp.Lazy], [])]
  [JoinColumn('ID_ALBUM', [])]
  FAlbum: Proxy<TAlbum>;

TAlbum = class
public
  [ManyValuedAssociation([], CascadeTypeAllRemoveOrphan, 'FAlbum')]
  property MediaFiles: TList<TMediaFile> read FMediaFiles write FMediaFiles;