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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 8
| plan_no | item_id |
|---|---|
| T190931 | 201022 |
| T190931 | 220933 |
| T190932 | 289338 |
| T190933 | 374882 |
| T190936 | 093022 |
| T190936 | 266679 |
| T190936 | 346762 |
| T190936 | 327392 |
SELECT 8
| plan_no | item_id | rownum |
|---|---|---|
| T190931 | 201022 | 1 |
| T190931 | 220933 | 2 |
| T190932 | 289338 | 1 |
| T190933 | 374882 | 1 |
| T190936 | 093022 | 1 |
| T190936 | 266679 | 2 |
| T190936 | 346762 | 3 |
| T190936 | 327392 | 4 |
SELECT 8