데이터 입출력 구현난도 중상
3번 · 주관식 · 5점
다음 테이블과 SQL문을 보고 출력값을 쓰시오.
SELECT COUNT(*)
FROM employee AS e
JOIN project AS p ON e.project_id = p.project_id
WHERE p.name IN (
SELECT name
FROM project
WHERE project_id IN (
SELECT project_id
FROM employee
GROUP BY project_id
HAVING COUNT(*) < 2
)
);| employee_id | name | project_id |
|---|---|---|
| 1 | Alice | 10 |
| 2 | Bob | 10 |
| 3 | Charlie | 20 |
| 4 | Dana | 30 |
| 5 | Ethan | 30 |
| project_id | name |
|---|---|
| 10 | Alpha |
| 20 | Beta |
| 30 | Gamma |