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CREATE TABLE turip_refs (check_id INT, name VARCHAR(5), ref_no CHAR(3));
INSERT INTO turip_refs VALUES
(10, 'alsak', 'xdr'),
(21, 'turin', 'xdr'),
(10, 'tend' , 'ymt'),
(21, 'turin', 'kuy');
SELECT * FROM turip_refs;
| check_id | name | ref_no |
|---|---|---|
| 10 | alsak | xdr |
| 21 | turin | xdr |
| 10 | tend | ymt |
| 21 | turin | kuy |
SELECT DISTINCT t1.*
FROM turip_refs t1
JOIN turip_refs t2 USING (ref_no)
WHERE t1.check_id != t2.check_id
-- AND another conditions
ORDER BY ref_no
-- , another criteria
| check_id | name | ref_no |
|---|---|---|
| 21 | turin | xdr |
| 10 | alsak | xdr |