replace(string, target, replacement)
select replace('hello world', 'world', 'there')
>> 결과 : hello there
sellect replace(job_id, 'engineer', '엔지니어')
from employees
>> 결과 : 엔지니어
sellect replace(replace(job_id, 'engineer', '엔지니어'), 'desinger', '디자이너')
from employees