Human Traffic of Stadium.md

⚙문제보기

🔎문제 풀이 MySQL

WITH t AS (
    SELECT t1.id, t1.visit_date, t1.people,
        id - ROW_NUMBER() OVER(ORDER BY id) AS grp 
    FROM stadium t1
    WHERE people >= 100
)

SELECT t.id, t.visit_date, t.people
FROM t
WHERE grp IN (SELECT grp FROM t GROUP BY grp HAVING COUNT(*) >=3);

WITH

• WITH [ 별명 ] AS ( SUB QUERY )
• 임시테이블 또는 가상 테이블의 개념.

ROW_NUMBER()

• 정렬 기준으로 행 번호를 매겨주는 함수