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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 7
CREATE TABLE
INSERT 0 3
| station_id | value | date |
|---|---|---|
| 001 | 10 | 2014-01-01 |
| 001 | null | 2014-01-02 |
| 001 | 30 | 2014-01-03 |
| 001 | null | 2014-01-04 |
| 002 | 40 | 2014-01-01 |
| 002 | null | 2014-01-02 |
| 002 | null | 2014-01-03 |
| 002 | null | 2014-01-04 |
| 003 | 20 | 2014-01-01 |
| 003 | null | 2014-01-02 |
| 003 | null | 2014-01-03 |
| 003 | null | 2014-01-04 |
SELECT 12