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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
| source | t_id | txt |
|---|---|---|
| sel | 1 | foo |
| sel | 2 | bar |
| sel | 3 | baz |
| up1 | 1 | foo1 |
| up3 | 2 | bar3 |
| up3 | 3 | baz3 |
| t | 1 | foo |
| t | 2 | bar |
| t | 3 | baz |
SELECT 9