Base de datos LeetCode 178. Clasificación de puntaje

178. Clasificación de puntaje

SELECT Score, 
    (
        SELECT COUNT(DISTINCT(b.Score))# 查看有多少个b.Score大于等于当前的a.Score
        FROM Scores AS b # 给Scores表取别名 
        WHERE b.Score>=a.Score
    ) AS Rank
FROM Scores AS a
ORDER BY Score DESC

Idea: DISTINCT primero y luego COUNT