Access the foreign key column in the child table.

[_Oleksiy_Penkov]

Hi.
I have a column declared in the master table as follows:

[ManyValuedAssociation([], CascadeTypeAllButRemove)]
[ForeignJoinColumn('ActionID', [])]
FFilesList : Proxy<TFilesList>;

How to access this column in the Details table at runtime since it is not visible in design time? I see that the column ActionID exists in the database.

[wlandgraf (Wagner Landgraf)]

@_Oleksiy_Penkov

How to access this column in the Details table at runtime since it is not visible in design time?

Unfortunately I didn't understand your question.
If you are asking about TAureliusDataset, here is how to access detail records in a many-valued association:

Data Binding - TAureliusDataset | TMS Aurelius documentation

[_Oleksiy_Penkov]

Ok, let me try to explain better.
I have a master table Items defined like this:

  [Entity]
  [Table('Items')]
  [Description('')]
  [Id('FId', TIdGenerator.IdentityOrSequence)]
  TItem = class
  private
    [Column('ID', [TColumnProp.Required, TColumnProp.NoInsert, TColumnProp.NoUpdate])]
    [Description('')]
    FId: Integer;
    ...
    [ManyValuedAssociation([], CascadeTypeAllButRemove)]
    [ForeignJoinColumn('ItemID', [])]
    FFilesList : Proxy<TFilesList>;

And a detailed table Files:

TFilesList = TList;

  [Entity]
  [Table('File')]
  [Description('')]
  [Id('FId', TIdGenerator.IdentityOrSequence)]
  TFile = class
  private
    [Column('Id', [TColumnProp.Required, TColumnProp.NoInsert, TColumnProp.NoUpdate])]
    [Description('')]
    FId: Integer;
    
    [Column('Description', [TColumnProp.Lazy])]
    [Description('')]
    FDescription: string;

    [Column('Name', [TColumnProp.Required, TColumnProp.Lazy])]
    [Description('')]
    FName: string;

The field ItemID is created in the Files table. My question is how to access this field? In particular, I need to get ItemID for a given Id inside the TFile class.
Something like this doesn't work:

  Result := FManager.Find<TItem>
    .Where(FDic.ID = FActionID)
    .List;

Because Result[0] doesn't contain field ItemID

[wlandgraf (Wagner Landgraf)]

You have to map the association as bidirectional, creating the other side of the association in the TFile class. There you create a Item: TItem association mapping and in the ManyValuedAssociation you modify it to point to that association:

    [ManyValuedAssociation([], CascadeTypeAllButRemove, 'FItem')]
    FFilesList : Proxy<TFilesList>;

It's explained here:

How to Access Parent Entity

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

And here:

Mapping | TMS Aurelius documentation

[_Oleksiy_Penkov]

Ok, I tried to follow the documentation, and declared the association in the master table as follows:

[Entity]
[Table('Items')]     
TItem = class
     private
       [ManyValuedAssociation([], CascadeTypeAllRemoveOrphan, 'FItem')]
       FFilesList: Proxy<TFilesList>;

And in TFile:

TFilesList = TList<TFile>;

 [Table('Files')]
TFile = class
private    
     [Association([TAssociationProp.Lazy], [])]
     [JoinColumn('ItemID', [])]
     FItem: Proxy<TItem>;

It works. Thanks!