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8 rows affected
| x | left_y | right_y |
|---|---|---|
| a | 1 | null |
| a | 2 | 2 |
| b | 4 | null |
| b | 5 | 5 |
| a | null | 3 |
| b | null | 6 |
8 rows affected
| x | left_y | right_y |
|---|---|---|
| a | 1 | null |
| a | 2 | 2 |
| b | 4 | null |
| b | 5 | 5 |
| a | null | 3 |
| b | null | 6 |