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CREATE TABLE tablename (`x` INTEGER, `y` INTEGER);
✓
INSERT INTO tablename (`x`, `y`) VALUES
('1', '1'),
('1', '3'),
('2', '2'),
('2', '3'),
('3', '1'),
('3', '2'),
('3', '3');
✓
SELECT x
FROM tablename
GROUP BY x
HAVING COUNT(DISTINCT y) = (SELECT COUNT(DISTINCT y) FROM tablename);
| x |
|---|
| 3 |
SELECT *
FROM tablename
WHERE x IN (
SELECT x
FROM tablename
GROUP BY x
HAVING COUNT(DISTINCT y) = (SELECT COUNT(DISTINCT y) FROM tablename)
);
| x | y |
|---|---|
| 3 | 1 |
| 3 | 2 |
| 3 | 3 |