DELETE FROM ITEM WHERE NOT EXISTS (SELECT ITEM_CODE FROM STOCK WHERE STOCK.ITEM_CODE = ITEM.ITEM_CODE);
DELETE FROM 
(SELECT ITEM.ITEM_CODE, LAST_DELIVERY_DATE, ACTUAL_AMT FROM ITEM INNER JOIN STOCK ON STOCK.ITEM_CODE = ITEM.ITEM_CODE
 WHERE ITEM.STOCK_MANAGEMENT_TYPE = 1
 AND ACTUAL_AMT = 0
 AND LAST_DELIVERY_DATE < date('2023-06-01', 'localtime', '-6 months')
);