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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?.
DROP TABLE
CREATE TABLE
INSERT 0 3
| month | count |
|---|---|
| 2018-01-01 | 2 |
| 2018-02-01 | 2 |
| 2018-03-01 | 2 |
| 2018-04-01 | 2 |
| 2018-05-01 | 2 |
| 2018-06-01 | 2 |
| 2018-07-01 | 2 |
| 2018-08-01 | 2 |
| 2018-09-01 | 2 |
| 2018-10-01 | 2 |
| 2018-11-01 | 2 |
| 2018-12-01 | 2 |
| 2019-01-01 | 2 |
| 2019-02-01 | 3 |
| 2019-03-01 | 3 |
| 2019-04-01 | 3 |
| 2019-05-01 | 3 |
| 2019-06-01 | 3 |
| 2019-07-01 | 3 |
| 2019-08-01 | 3 |
| 2019-09-01 | 3 |
| 2019-10-01 | 3 |
| 2019-11-01 | 3 |
| 2019-12-01 | 3 |
| 2020-01-01 | 3 |
| 2020-02-01 | 2 |
| 2020-03-01 | 2 |
| 2020-04-01 | 2 |
| 2020-05-01 | 2 |
| 2020-06-01 | 2 |
| 2020-07-01 | 2 |
| 2020-08-01 | 1 |
| 2020-09-01 | 1 |
| 2020-10-01 | 1 |
| 2020-11-01 | 1 |
| 2020-12-01 | 1 |
SELECT 36