WITH A AS(
SELECT
*,
DATE(FIRST_VALUE(LOGIN_DATETIME)
OVER(
    PARTITION BY MEMBER_CODE
    ORDER BY LOGIN_DATETIME
    )
)AS FL
FROM ACCESS_LOG
)

SELECT FL AS FIRST_LOGIN,
COUNT(*) AS MEMBER_CNT
FROM
(SELECT MEMBER_CODE,FL
FROM A
WHERE FL BETWEEN '2023-08-01' AND '2023-08-31'
GROUP BY MEMBER_CODE)
GROUP BY FL
ORDER BY 1 DESC
;