DELETE FROM ITEM
WHERE
STOCK_MANAGEMENT_TYPE = 1
AND
(NOT EXISTS 
(SELECT 
 ITEM_CODE
 FROM
 STOCK
WHERE STOCK.ITEM_CODE = ITEM.ITEM_CODE)
OR EXISTS
(SELECT
 ITEM_CODE
 FROM STOCK
 WHERE STOCK.ITEM_CODE = ITEM.ITEM_CODE
GROUP BY ITEM_CODE
AND
LAST_DELIVERY_DATE IS NOT NULL
HAVING
MAX(LAST_DELIVERY_DATE)<= DATE('2023-06-01', '-6 months')
AND
SUM(ACTUAL_AMT)=0))