FireDAC TFDBatchMove custom Mappings ..

FireDAC TFDBatchMove custom Mappings ..

Has anyone have a sample of creating custom mappings for moving data using TFDBatchMove with a TFDBatchMoveSQLReader and TFDBatchMoveSQLWriter?

I get an error: 'access violation at .. :read of address ..'
I wrote ..

var
  I: Integer;
  ABatchMoveMappingItem: TFDBatchMoveMappingItem;
begin
    fdbatchmove.Mappings.Clear;
    fdmetaSource.First;
    fdmetaTarget.First;
    while NOT fdmetaSource.Eof do
    begin
      ABatchMoveMappingItem := fdbatchmove.Mappings.Add;
      ABatchMoveMappingItem.SourceFieldName := fdmetaSource.FieldByName('COLUMN_NAME').AsString;
      ABatchMoveMappingItem.DestinationFieldName := fdmetaTarget.FieldByName('COLUMN_NAME').AsString;
      fdmetaSource.Next;
      fdmetaTarget.Next;
    end;

    fdbatchmove.Execute;
  end;