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8 rows affected
| Id | ItemId | startr | endr | prev_endr | grp |
|---|---|---|---|---|---|
| 1 | 1 | 1 | 10 | null | 1 |
| 2 | 1 | 11 | 20 | 10 | 1 |
| 3 | 1 | 21 | 30 | 20 | 1 |
| 4 | 1 | 40 | 50 | 30 | 2 |
| 5 | 1 | 51 | 60 | 50 | 2 |
| 6 | 1 | 61 | 70 | 60 | 2 |
| 7 | 1 | 80 | 90 | 70 | 3 |
| 8 | 1 | 100 | 200 | 90 | 4 |