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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 1
| cola | colb | colc | cold |
|---|---|---|---|
| 1 | null | null | null |
| 1 | 2 | null | null |
| 1 | 2 | 3 | null |
| 1 | 2 | 3 | 4 |
SELECT 4