with sales as (
select
    1 as join_code
    ,ITEM_CODE as CODE
    ,ITEM_NAME as NAME
    ,sum(UNITPRICE*SALES_QTY) as SAL_AMT
from SALES 
join SALES_DTL using(SALES_NO)
join ITEM using(ITEM_CODE)
where
    date(SALES_DATE) between '2023-06-01' and '2023-06-30'
group by 1,2
)

,total_sales as (
select 
    1 as join_code
    ,sum(SAL_AMT) as TOTAL_SAL_AMT
from sales
group by 1
)

-- ,sal_comp as (
select
    CODE
    ,NAME
    ,SAL_AMT
    ,TOTAL_SAL_AMT
from
    sales
join
    total_sales using(join_code)
-- )