다음 중 "연봉(SAL)이 3,000을 초과하면서, 상위 직급자(관리자, MGR)가 존재하는 사원"을 찾는 SQL로 가장 적절하지 않은 것은?
- 1
SELECT EMP_ID, EMP_NAME, SAL FROM EMP E WHERE SAL > 3000 AND EXISTS ( SELECT 1 FROM EMP M WHERE M.EMP_ID = E.MGR_ID );
- 2
SELECT EMP_ID, EMP_NAME, SAL FROM EMP WHERE SAL > 3000 AND MGR_ID IN ( SELECT EMP_ID FROM EMP );
- 3
SELECT EMP_ID, EMP_NAME, SAL FROM EMP E WHERE SAL > 3000 AND NOT EXISTS ( SELECT 1 FROM EMP M WHERE M.EMP_ID <> E.MGR_ID );
- 4
SELECT E1.EMP_ID, E1.EMP_NAME, E1.SAL FROM EMP E1, EMP E2 WHERE E1.MGR_ID = E2.EMP_ID AND E1.SAL > 3000;
꿈라CBT