DELETE
FROM ITEM
WHERE NOT EXISTS (SELECT 1 FROM STOCK S WHERE S.ITEM_CODE = ITEM.ITEM_CODE);

WITH T as (
SELECT
ITEM_CODE
FROM STOCK
WHERE LAST_DELIVERY_DATE < '2023-01-01' or LAST_DELIVERY_DATE IS NULL
GROUP BY ITEM_CODE
)

DELETE
FROM ITEM
WHERE ITEM_CODE IN (SELECT ITEM_CODE FROM T)
  and STOCK_MANAGEMENT_TYPE = '1';