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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 6
| parent_id | child_id | level | entity |
|---|---|---|---|
| 11 | 22 | 4 | a |
| 22 | 33 | 4 | a |
| 33 | 44 | 4 | a |
| 11 | 22 | 7 | b |
| 22 | 33 | 4 | b |
| 33 | 44 | 4 | b |
SELECT 6