select
    ITEM.*
from
    ITEM
    inner join
        (
            select
                ITEM_CODE,
                MAX(case when LAST_DELIVERY_DATE isnull then '2023-06-01' else LAST_DELIVERY_DATE end) as MAX_DD,
                SUM(ACTUAL_AMT) as TOTAL_AMT
            from
                STOCK
            group by
                ITEM_CODE
            having
                MAX_DD > datetime('2023-06-01', '-6 months')
                or TOTAL_AMT != 0
        ) as EX_STOCK
        using(ITEM_CODE)
where
    STOCK_MANAGEMENT_TYPE = 1 ;