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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
CREATE TABLE
INSERT 0 3
INSERT 0 4
| d | code | coalesce |
|---|---|---|
| 2022-01-01 | WEB | 2 |
| 2022-01-01 | MOBILE | 0 |
| 2022-01-01 | DESKTOP | 0 |
| 2022-01-02 | WEB | 1 |
| 2022-01-02 | MOBILE | 1 |
| 2022-01-02 | DESKTOP | 0 |
| 2022-01-03 | WEB | 0 |
| 2022-01-03 | MOBILE | 0 |
| 2022-01-03 | DESKTOP | 0 |
| 2022-01-04 | WEB | 0 |
| 2022-01-04 | MOBILE | 0 |
| 2022-01-04 | DESKTOP | 0 |
| 2022-01-05 | WEB | 0 |
| 2022-01-05 | MOBILE | 0 |
| 2022-01-05 | DESKTOP | 0 |
SELECT 15