maria
strt_to_date 포맷은 입력 된 포맷과 동일해야함 date_format은 출력 될 포맷임 select str_to_date('2023-01-01','%Y-%m-%d') -- 2023-01-01 , str_to_date('20230101','%Y%m%d') -- 2023-01-01 , str_to_date('20230101 13:11:11','%Y%m%d %H:%i:%s') -- 2023-01-01 13:11:11.000 , str_to_date('2023-01-01 13:11:11','%Y-%m-%d %H:%i:%s') -- 2023-01-01 13:11:11.000 , date_format('2023-01-01 13:11:11', '%Y-%m-%d %H:%i:%s') -- 2023-01-01 1..