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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 6
| carrier | id | d_date | |
|---|---|---|---|
| email_1 | car_1 | 1 | 2019-02-08 00:00:00 |
| email_1 | car_1 | 1 | 2019-02-09 00:00:00 |
| email_1 | car_1 | 2 | 2019-02-10 00:00:00 |
| email_1 | car_2 | 2 | 2019-02-11 00:00:00 |
| email_2 | car_3 | 3 | 2019-02-09 00:00:00 |
| email_2 | car_4 | 4 | 2019-02-09 00:00:00 |
SELECT 6
| carrier | id | date | |
|---|---|---|---|
| email_1 | car_1 | 2 | 2019-02-10 00:00:00 |
| email_2 | car_4 | 4 | 2019-02-09 00:00:00 |
| email_1 | car_1 | 1 | 2019-02-08 00:00:00 |
| email_1 | car_2 | 2 | 2019-02-11 00:00:00 |
| email_2 | car_3 | 3 | 2019-02-09 00:00:00 |
SELECT 5