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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 x (y _float8)
CREATE TABLE
insert into x values (array[1.0, 2.0, 3.5])
INSERT 0 1
alter table x alter column y set data type int4 using (y[1]::int)
ALTER TABLE
table x
| y |
|---|
| 1 |
SELECT 1