Postgres 14

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.

Help with an interesting Postgres question: Why isn't an Index Only Scan used on a partition accessed via the parent table?.

CREATE TABLE tablename (
name text,
col1 int,
col2 int,
col3 int,
col4 int,
col5 int
);
WITH generator AS (
    SELECT array_agg(gen.i ORDER BY random()) AS numbers
     FROM generate_series(1, 5) gen(i) -- range of numbers
    CROSS
     JOIN generate_series(1, 5) rows(i) -- number of rows
    GROUP BY rows.i
)
INSERT INTO tablename
(name, col1, col2, col3, col4, col5)
SELECT substr(md5(random()::text), 0, 15) AS name
     , gen.numbers[1]
     , gen.numbers[2]
     , gen.numbers[3]
     , gen.numbers[4]
     , gen.numbers[5]
  FROM generator gen
  

5 rows affected

SELECT * FROM tablename


name
col1
col2
col3
col4
col5


3cef3ab73e5490
1
5
2
3
4

589a71e4041878
1
3
4
2
5

c3f0aab14da6e4
5
2
3
4
1

7a13a7d0a457de
5
1
2
4
3

7617526841eec9
3
5
4
2
1

name	col1	col2	col3	col4	col5
3cef3ab73e5490	1	5	2	3	4
589a71e4041878	1	3	4	2	5
c3f0aab14da6e4	5	2	3	4	1
7a13a7d0a457de	5	1	2	4	3
7617526841eec9	3	5	4	2	1