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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 your_table(fixtures) as values
('{ "fixture_1":"fixture1"
,"fixture_2":"fixture2"
,"fixture_321":"fixture321"}');
select regexp_substr(json_object_keys(fixtures::json),'(\d+)$')::int as "ID"
from your_table;
SELECT 1
| ID |
|---|
| 1 |
| 2 |
| 321 |
SELECT 3