꿈라CBT어느 부서에도 속하지 않는 직원을 조회하는 SQL로 가장 적절한 것은?
보기
[EMP]
| EMPNO | ENAME | DEPTNO |
|---|---|---|
| 1 | A | 10 |
| 2 | B | NULL |
| 3 | C | 99 |
[DEPT]
| DEPTNO | DNAME |
|---|---|
| 10 | 영업 |
| 20 | 인사 |
- 1SELECT * FROM EMP E, DEPT D WHERE E.DEPTNO = D.DEPTNO;
- 2SELECT * FROM EMP WHERE DEPTNO IS NULL OR DEPTNO NOT IN (SELECT DEPTNO FROM DEPT);
- 3SELECT * FROM EMP E LEFT JOIN DEPT D ON E.DEPTNO = D.DEPTNO WHERE D.DEPTNO IS NOT NULL;
- 4SELECT * FROM EMP WHERE DEPTNO NOT IN (SELECT DEPTNO FROM DEPT);