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| id | num | xdate |
|---|---|---|
| 1 | A1 | 201703 |
| 2 | B1 | 201608 |
| 3 | A1 | 202104 |
| 4 | C1 | 202006 |
| 5 | A1 | 201610 |
| 6 | B1 | 201703 |
| id | num | xdate |
|---|---|---|
| 3 | A1 | 202104 |
| 1 | A1 | 201703 |
| 6 | B1 | 201703 |
| 2 | B1 | 201608 |
| 4 | C1 | 202006 |