[HackerRank SQL] Top Competitors

문제 link
https://www.hackerrank.com/challenges/full-score/problem

Code link
https://github.com/JamesJung01/Hackerrank_sql/blob/main/02_Medium/Top_Competitors.sql

SELECT h.hacker_id, 
       h.name
FROM submissions AS s 
JOIN challenges AS c
    ON s.challenge_id = c.challenge_id
JOIN difficulty AS d
    ON c.difficulty_level = d.difficulty_level
JOIN hackers AS h
    ON s.hacker_id = h.hacker_id
WHERE s.score = d.score
AND c.difficulty_level = d.difficulty_level
GROUP BY h.hacker_id, h.name
HAVING COUNT(s.hacker_id) > 1
ORDER BY COUNT(s.hacker_id) DESC, s.hacker_id ASC