https://velog.io/@joshuara7235/ISSUEs-JPA%EB%A1%9C-%EC%83%9D%EC%84%B1%ED%95%9C-entity-column%EC%97%90%EC%84%9C-unique-%EC%A0%9C%EC%95%BD%EC%A1%B0%EA%B1%B4-%EC%82%AD%EC%A0%9C%ED%95%98%EA%B8%B0
spring.jap.hibernate.ddl-auto : update