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https://leetcode.com/problems/count-salary-categories/description/?envType=study-plan-v2&envId=top-sql-50 Count Salary Categories - LeetCode Can you solve this real interview question? Count Salary Categories - Table: Accounts +-------------+------+ | Column Name | Type | +-------------+------+ | account_id | int | | income | int | +-------------+------+ account_id is the primary key (column wi ..

문제 링크 https://leetcode.com/problems/students-and-examinations/description/?envType=study-plan-v2&envId=top-sql-50 Students and Examinations - LeetCode Can you solve this real interview question? Students and Examinations - Table: Students +---------------+---------+ | Column Name | Type | +---------------+---------+ | student_id | int | | student_name | varchar | +---------------+---------+ stud..

문제링크: www.hackerrank.com/challenges/full-score/problem?isFullScreen=true Top Competitors | HackerRank Query a list of top-scoring hackers. www.hackerrank.com Table 설명 * Hackers: 전체 hackers 정보 * Difficulty: 문제의 난이도 별 Full score 정보 * Challenges: 문제와, 문제를 제작한 Hacker 정보, 문제의 난이도 정보 * Submissions: 문제를 제출한 사람의 정보와, 제출 시 score 정보 문제 설명 코딩테스트 제출자 중 full score 맞은 문제가 한개보다 많은 (2개 이상) 인 참가자의 hacker_id와, na..

문제 출처: leetcode.com/problems/department-highest-salary/ Department Highest Salary - LeetCode Level up your coding skills and quickly land a job. This is the best place to expand your knowledge and get prepared for your next interview. leetcode.com 문제. 각 부서에서 salary 가장 높은 사람 뽑기 출력 형태 Solution1. FROM 절에서 Subquery + MAX() 윈도우함수 1) subquery에서 max() 윈도우함수를 써서 부서 별 가장 높은 salary를 구해준다 (M_Salary) subque..

문제 링크: www.hackerrank.com/challenges/symmetric-pairs/problem?h_r=internal-search Symmetric Pairs | HackerRank Write a query to output all symmetric pairs in ascending order by the value of X. www.hackerrank.com 문제. 짝꿍찾기 - X1 = Y2 and X2 = Y1 - X1