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CREATE TABLE test (
ID INT,
SCORE INT
);
INSERT INTO test VALUES
(1, 5),
(1, 6),
(2, 9),
(2, 5),
(2, 6),
(3, 5),
(3, 7);
SELECT t1.SCORE, t2.SCORE, SUM(t1.ID = t2.ID)
FROM test t1 JOIN test t2
WHERE t1.SCORE <> t2.SCORE AND t1.SCORE < t2.SCORE
GROUP BY t1.SCORE, t2.SCORE
ORDER BY t1.SCORE, t2.SCORE
| SCORE | SCORE | SUM(t1.ID = t2.ID) |
|---|---|---|
| 5 | 6 | 2 |
| 5 | 7 | 1 |
| 5 | 9 | 1 |
| 6 | 7 | 0 |
| 6 | 9 | 1 |
| 7 | 9 | 0 |