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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?.
SELECT 4
| user_id | start_date | end_date | has_overlap_flag |
|---|---|---|---|
| 1 | 2019-01-01 | 2019-01-31 | t |
| 2 | 2019-01-15 | 2019-01-17 | t |
| 3 | 2019-01-29 | 2019-02-04 | t |
| 4 | 2019-02-05 | 2019-02-10 | f |
SELECT 4