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CREATE TABLE tokens ( id, token ) AS
SELECT 1, 10 FROM DUAL UNION ALL
SELECT 2, 3 FROM DUAL UNION ALL
SELECT 3, 0 FROM DUAL UNION ALL
SELECT 4, -1 FROM DUAL UNION ALL
SELECT 5, -9 FROM DUAL;
5 rows affected
SELECT id,
GREATEST( token, 0 ) AS token
FROM tokens;
| ID | TOKEN |
|---|---|
| 1 | 10 |
| 2 | 3 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |