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select employee_id, e.department_id, d.department_name from employees e, departments d where e.department_id = d.department_id and last_name = 'King'; select employee_id, e.department_id, d.department_name from employees e INNER JOIN departments d on e.department_id = d.department_id where last_name = 'King'; - 3개 이상 조인 -> 테이블1 join 테이블2 on 공통컬럼1 = 공통컬럼1 join 테이블 3 on 공통컬럼2 = 공통컬럼 2 ------------..