DELETE FROM 
ITEM 
WHERE 
NOT EXISTS(SELECT 1 FROM STOCK S WHERE S.ITEM_CODE = ITEM.ITEM_CODE)
OR
EXISTS
(SELECT 1 FROM 
 (SELECT ITEM_CODE,MAX(LAST_DELIVERY_DATE) as LAST_DATE ,SUM(ACTUAL_AMT) 

 as AMT FROM STOCK GROUP BY ITEM_CODE 
 )B
WHERE B.ITEM_CODE = ITEM.ITEM_CODE AND LAST_DATE <= datetime('2023-06-01','-6 months')

AND AMT=0
)
;