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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 8
| customer_id | timestamp |
|---|---|
| 5544 | 2022-01-01 |
| 5544 | 2022-04-01 |
| 5544 | 2022-04-02 |
| 6778 | 2021-01-01 |
| 6778 | 2022-01-01 |
| 6778 | 2022-02-04 |
SELECT 6