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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 2
| A_a | B_a | A_b | B_b |
|---|---|---|---|
| 4 | 3 | 4 | 5 |
| 2 | 5 | 3 | 1 |
SELECT 2
| upper_case | lower_case | value |
|---|---|---|
| A | a | 4 |
| A | a | 2 |
| B | a | 3 |
| B | a | 5 |
| A | b | 3 |
| A | b | 4 |
| B | b | 5 |
| B | b | 1 |
SELECT 8