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select version();
| version() |
|---|
| 5.5.62 |
CREATE TABLE test( id INT, a INT, b INT );
INSERT INTO test VALUES
(1,1,3),(2,2,3),(3,3,1);
SELECT * FROM test;
| id | a | b |
|---|---|---|
| 1 | 1 | 3 |
| 2 | 2 | 3 |
| 3 | 3 | 1 |
SELECT least(a, b) , greatest (a,b)
FROM test
GROUP BY least(a, b) , greatest (a,b)
| least(a, b) | greatest (a,b) |
|---|---|
| 1 | 3 |
| 2 | 3 |