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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 tbl (fid int, result int, time int);
CREATE TABLE
insert into tbl values
(1, 10, 100),
(2, 9, 90),
(3, 8, 80),
(3, 7, 70),
(3, 100, 60),
(4, 5, 50)
INSERT 0 6
select fid, result, time
from tbl where time in (select max(time) from tbl group by fid)
order by fid
| fid | result | time |
|---|---|---|
| 1 | 10 | 100 |
| 2 | 9 | 90 |
| 3 | 8 | 80 |
| 4 | 5 | 50 |
SELECT 4