SQLD CBT 기출문제 예상문제 890번

다음 문제를 풀어보세요.

다음 보기 중 LAST_VALUE 윈도우 함수를 사용하여 각 사원별로 부서 내 최고 급여를 올바르게 출력하는 SQL로 가장 적절한 것을 고르시오.

[테이블 구조]
CREATE TABLE EMP (
  EMPNO INT,
  ENAME VARCHAR(10),
  DEPTNO INT,
  SAL INT
);

SELECT ENAME, DEPTNO, SAL, 
       LAST_VALUE(SAL) OVER (PARTITION BY DEPTNO ORDER BY SAL) AS MAX_SAL 
FROM EMP;

SELECT ENAME, DEPTNO, SAL, 
       LAST_VALUE(SAL) OVER (PARTITION BY DEPTNO ORDER BY SAL ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) AS MAX_SAL 
FROM EMP;

SELECT ENAME, DEPTNO, SAL, 
       LAST_VALUE(SAL) OVER (PARTITION BY DEPTNO ORDER BY SAL ROWS BETWEEN CURRENT ROW AND CURRENT ROW) AS MAX_SAL 
FROM EMP;

SELECT ENAME, DEPTNO, SAL, 
       LAST_VALUE(SAL) OVER (PARTITION BY DEPTNO ORDER BY SAL DESC ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING) AS MAX_SAL 
FROM EMP;