3767. Find Students Who Improved
My accepted SQL solution to LeetCode problem 3767, Find Students Who Improved, running in 280ms.
- Difficulty: Medium
- SQL
- Runtime 280ms
- Memory 0.0B
- Updated
Read the problem on LeetCode View on GitHub
The problem statement is LeetCode’s and stays on their site. What follows is my accepted solution.
SQL
Accepted on LeetCode — runtime 280ms, memory 0.0B, accepted 2025-12-31.
# Write your MySQL query statement below
WITH first_scores AS (
SELECT student_id, subject, score AS first_score, exam_date
FROM Scores s1
WHERE exam_date = (
SELECT MIN(exam_date) FROM Scores s2
WHERE s1.student_id = s2.student_id AND s1.subject = s2.subject
)
),
latest_scores AS (
SELECT student_id, subject, score AS latest_score, exam_date
FROM Scores s1
WHERE exam_date = (
SELECT MAX(exam_date) FROM Scores s2
WHERE s1.student_id = s2.student_id AND s1.subject = s2.subject
)
)
SELECT f.student_id, f.subject, f.first_score, l.latest_score
FROM first_scores f
JOIN latest_scores l ON f.student_id = l.student_id AND f.subject = l.subject
WHERE f.exam_date < l.exam_date AND l.latest_score > f.first_score
ORDER BY f.student_id, f.subject;