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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?.
SELECT 6
| date | id | day_num |
|---|---|---|
| 2019-01-01 | 1 | 1 |
| 2019-01-02 | 2 | 2 |
| 2019-01-02 | 3 | 2 |
| 2019-01-04 | 4 | 3 |
| 2019-01-07 | 5 | 4 |
| 2019-01-07 | 6 | 4 |
SELECT 6