DELETE FROM ITEM
WHERE 
    ITEM.STOCK_MANAGEMENT_TYPE = 1
    AND (
        ITEM.ITEM_CODE NOT IN (SELECT ITEM_CODE FROM STOCK) 
        OR ITEM.ITEM_CODE IN (
            SELECT S.ITEM_CODE FROM STOCK AS S
            GROUP BY S.ITEM_CODE
            HAVING MAX(
                CASE WHEN S.LAST_DELIVERY_DATE IS NULL THEN "2023-06-01"
                ELSE S.LAST_DELIVERY_DATE
                END
            ) <= DATE('2023-06-01', '-6 months') 
            AND SUM(S.ACTUAL_AMT) = 0
        )
    );