DELETE FROM ITEM
WHERE STOCK_MANAGEMENT_TYPE = 1 AND
(ITEM_CODE NOT IN (SELECT ITEM_CODE FROM STOCK)
OR ITEM_CODE IN
(SELECT ITEM_CODE FROM STOCK GROUP BY ITEM_CODE
HAVING MAX(IFNULL(LAST_DELIVERY_DATE, '2999-12-31')) <= DATE('2023-06-01', '-6 months') AND
SUM(ACTUAL_AMT) = 0));