[REFACTOR] 블랙홀 컬럼 추출

[kenu]

select username, active, blackholed_at, datediff(blackholed_at, now()) toblack from
(select username, active,
str_to_date(json_extract(data, '$.cursus_users[1].blackholed_at'),'"%Y-%m-%dT%T.%fZ"') blackholed_at
from users where active = true) a
where datediff(blackholed_at, now()) > -10