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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 12
| tracking_id | measure_value_gender | measure_value_age | measure_name |
|---|---|---|---|
| 1 | Male | null | gender |
| 1 | null | 10 | age |
| 2 | Male | null | gender |
| 2 | null | 12 | age |
| 3 | Female | null | gender |
| 3 | null | 9 | age |
| 4 | Male | null | gender |
| 4 | null | 15 | age |
| 5 | Female | null | gender |
| 5 | null | 16 | age |
| 6 | Female | null | gender |
| 6 | null | 14 | age |
SELECT 12
| age_range | male_count | female_count |
|---|---|---|
| 0 - 12 | 2 | 1 |
| 13 - 17 | 1 | 2 |
SELECT 2