오늘 한 일은,SQL 공부[코드카타] 3문제 풀기 (107~109번)파이썬 공부[파이썬 문제풀이] 기초 관통 실습 풀기[머신러닝 소프트랜딩] 수강하기[기초 통계학] 2주차 수강하기[수준별 학습반 - standard] OT 수강하기 SQL 공부: [코드카타] SQL 문제 풀기 (107~109번)107. (1789) Primary Department for Each EmployeeEmployees can belong to multiple departments. When the employee joins other departments, they need to decide which department is their primary department.Note that when an employee belon..