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| avg(1.0*c) over (order by id rows between 1 preceding and current row) |
|---|
| 1.00000 |
| 1.50000 |
| 2.50000 |
| 3.50000 |
| avg(1.0*c) over (order by id rows between 1 preceding and current row) |
|---|
| 1.00000 |
| 1.50000 |
| 2.50000 |
| 3.50000 |