SQLD CBT 기출문제 예상문제 942번

다음 문제를 풀어보세요.

다음 보기 중 실행결과가 다른 SQL을 고르시오.

[테이블 구조 및 데이터]
EMP



EMP_ID
DEPT_ID
MGR_ID




1
10
NULL


2
10
1


3
20
1


4
20
2

SELECT A.EMP_ID
FROM   EMP A LEFT OUTER JOIN EMP B
ON     A.EMP_ID = B.MGR_ID
AND    B.EMP_ID IS NULL
ORDER  BY A.EMP_ID;

SELECT A.EMP_ID
FROM   EMP A 
WHERE  A.EMP_ID NOT IN ( SELECT B.MGR_ID FROM EMP B WHERE B.MGR_ID IS NOT NULL )
ORDER  BY A.EMP_ID;

SELECT A.EMP_ID
FROM   EMP A 
WHERE  NOT EXISTS ( SELECT 1 FROM EMP B WHERE A.EMP_ID = B.MGR_ID )
ORDER  BY A.EMP_ID;

SELECT EMP_ID
FROM   EMP 
MINUS
SELECT MGR_ID
FROM   EMP 
ORDER  BY EMP_ID;