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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?.
CREATE TABLE
INSERT 0 22
| year | month | count(distinct user_id) |
|---|---|---|
| 2019 | 11 | 0 |
| 2019 | 12 | 1 |
| 2020 | 01 | 1 |
| 2020 | 02 | 2 |
| 2020 | 03 | 2 |
| 2020 | 04 | 0 |
| 2020 | 05 | 2 |
| 2020 | 06 | 2 |
| 2020 | 07 | 2 |
| 2020 | 08 | 1 |
| 2020 | 09 | 1 |
| 2020 | 10 | 2 |
| 2020 | 11 | 2 |
| 2020 | 12 | 2 |
SELECT 14