WITH STOCK_INFO AS (
    SELECT ITEM_CODE
          ,MAX(LAST_DELIVERY_DATE) AS LAST_DELIVERY_DATE
          ,SUM(ACTUAL_AMT) AS ACTUAL_AMT
         FROM STOCK
        GROUP BY ITEM_CODE
        ORDER BY ITEM_CODE
)
SELECT a.*
    FROM ITEM AS a
    JOIN STOCK_INFO AS b
    ON a.ITEM_CODE = b.ITEM_CODE
    WHERE (LAST_DELIVERY_DATE > DATE('2022-12-01') OR LAST_DELIVERY_DATE IS NULL)
    AND ACTUAL_AMT >0
    AND STOCK_MANAGEMENT_TYPE = 1

UNION ALL
SELECT *
    FROM ITEM
    WHERE STOCK_MANAGEMENT_TYPE = 0