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| id | col1 | col2 | col3 | col4 | lvl |
|---|---|---|---|---|---|
| 1 | a | b | c | null | 3 |
| 2 | a | b | null | null | 2 |
| 3 | a | b | c | d | 4 |
| id | col1 | col2 | col3 | col4 | lvl |
|---|---|---|---|---|---|
| 1 | c | b | a | null | 3 |
| 2 | b | a | null | null | 2 |
| 3 | d | c | b | a | 4 |
| id | col1 | col2 | col3 | col4 | lvl |
|---|---|---|---|---|---|
| 1 | a | b | c | null | 3 |
| 2 | a | b | null | null | 2 |
| 3 | a | b | c | d | 4 |
| id | col1 | col2 | col3 | col4 | lvl |
|---|---|---|---|---|---|
| 1 | c | b | a | null | 3 |
| 2 | b | a | null | null | 2 |
| 3 | d | c | b | a | 4 |