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            <h2 id="problem">Problem</h2><figure><a href="https://leetcode.com/problems/students-and-examinations/description/"><div><p>LeetCode - The World’s Leading Online Programming Learning Platform</p><p>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.</p><p><img src="https://leetcode.com/favicon.ico" alt=""><span>LeetCode</span></p></div><p><img src="https://leetcode.com/static/images/LeetCode_Sharing.png" alt=""></p></a></figure><h2 id="solution">Solution</h2><pre><code>SELECT Students.student_id, Students.student_name, Subjects.subject_name, IFNULL(cnt, 0) as attended_exams
FROM Students
CROSS JOIN Subjects
LEFT JOIN (
    SELECT student_id, subject_name, COUNT(*) as cnt FROM Examinations GROUP BY student_id, subject_name
) as Temp ON Subjects.subject_name = Temp.subject_name AND Students.student_id = Temp.student_id
ORDER BY student_id, subject_name</code></pre>
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일시불 프로그래밍

Problem
Solution
SELECT Students.student_id, Students.student_name, Subjects.subject_name, IFNULL(cnt, 0) as attended_exams
FROM Students
CROSS JOIN Subjects
LEFT JOIN (
    SELECT student_id, subject_name, COUNT(*) as cnt FROM Examinations GROUP BY student_id, subject_name
) as Temp ON Subjects.subject_name = Temp.subject_name AND Students.student_id = Temp.student_id
ORDER BY student_id, subject_name

Leetcode - 1280. Students and Examinations

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