WITH SeqTable AS (
    SELECT '2022-08-01' AS SEQ
    UNION ALL
    SELECT date(SEQ, '1 day') FROM SeqTable WHERE SEQ < '2022-08-31'
)
select
    SEQ as REGIST_DATE
    -- ,strftime('%w', SEQ) as DAY -- 0=Sun
    ,case
        when strftime('%w', SEQ)='0' then '日'
        when strftime('%w', SEQ)='1' then '月'
        when strftime('%w', SEQ)='2' then '火'
        when strftime('%w', SEQ)='3' then '水'
        when strftime('%w', SEQ)='4' then '木'
        when strftime('%w', SEQ)='5' then '金'
        when strftime('%w', SEQ)='6' then '土'
        end as WK
    ,case when TOTAL is null then 0 else TOTAL end as TOTAL
from
    SeqTable S
    left outer join
        (select 
            date(CONFIRMED_AT) as DAY
            ,count(*) as TOTAL
        from USERS where VALID_FLG='1'
        group by 1) U
        on
            S.SEQ=DAY
order by 1,2
;