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Help with an interesting Postgres question: Why isn't an Index Only Scan used on a partition accessed via the parent table?.
11 rows affected
| id | day | price | cumsum | grp |
|---|---|---|---|---|
| 1 | 1 | 40 | 40 | 0 |
| 2 | 1 | 40 | 80 | 0 |
| 3 | 1 | 40 | 120 | 1 |
| 4 | 1 | 40 | 160 | 2 |
| 5 | 1 | 40 | 200 | 2 |
| 6 | 1 | 40 | 240 | 3 |
| 7 | 2 | 40 | 40 | 0 |
| 8 | 2 | 40 | 80 | 0 |
| 9 | 2 | 40 | 120 | 1 |
| 10 | 2 | 40 | 160 | 2 |
| 11 | 2 | 40 | 200 | 2 |