go_block('selected_stock_list');
first_record;
:selected_stock_list.stock_id   := '1001';
:selected_stock_list.stock_desc := 'AAA';
next_record;
:selected_stock_list.stock_id   := '1002';
:selected_stock_list.stock_desc := 'BBB';
next_record;
:selected_stock_list.stock_id   := '1003';
:selected_stock_list.stock_desc := 'CCC';
first_record;

go_block('SELECTED_STOCK_LIST');
first_record;
loop
   if :selected_stock_list.stock_id is not null then
     --message('abc');
     message('stock_id:'||nvl(:selected_stock_list.stock_id,'XXX')); pause;
  end if;
  if :system.last_record = 'TRUE' then
    exit;  -- reached last record so exit loop
  else
    next_record;
  end if;
end loop;