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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?.
| subscription_id | dt | amount_monthly |
|---|---|---|
| 1382 | 2017-09-01 | 12.67 |
| 1382 | 2017-10-01 | 12.67 |
| 1382 | 2017-11-01 | 12.67 |
| 1383 | 2018-02-01 | 8.33 |
| 1383 | 2018-03-01 | 8.33 |
| 1383 | 2018-04-01 | 8.33 |
| 1383 | 2018-05-01 | 8.33 |
| 1383 | 2018-06-01 | 8.33 |
| 1383 | 2018-07-01 | 8.33 |
SELECT 9