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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 random() as rnd union all
select random() as rnd
| rnd |
|---|
| 0.5080853115712636 |
| 0.6200751818051424 |
SELECT 2
WITH
test_a as ( select random() ),
test_b as ( select * from test_a )
select * from test_a
union all
select * from test_b
| random |
|---|
| 0.5410845640785207 |
| 0.5410845640785207 |
SELECT 2