개발은 너무해

create table temp_nation as select 'Seoul' city, 'Korea' country from dual union all select 'Busan' city, 'Korea' country from dual union all select 'Inchon' city, 'Korea' country from dual union all select 'LA' city, 'America' country from dual union all select 'Newyork' city, 'America' country from dual union all select 'Mexicocity' city, 'Mexico' country from dual ; select country, substr(max..