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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 3
| child_id | parent_id | lvl |
|---|---|---|
| 3 | 3 | 1 |
| 3 | 2 | 2 |
| 3 | 1 | 3 |
SELECT 3