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| X1 | X2 | NOT_DISTINCT |
|---|---|---|
| 1 | 1 | 1 |
| 1 | 2 | 0 |
| 1 | null | 0 |
| 2 | 1 | 0 |
| 2 | 2 | 1 |
| 2 | null | 0 |
| null | 1 | 0 |
| null | 2 | 0 |
| null | null | 1 |
| X1 | X2 | NOT_DISTINCT |
|---|---|---|
| 1 | 1 | 1 |
| 1 | 2 | 0 |
| 1 | null | 0 |
| 2 | 1 | 0 |
| 2 | 2 | 1 |
| 2 | null | 0 |
| null | 1 | 0 |
| null | 2 | 0 |
| null | null | 1 |