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?.
drop table if exists company;
create table company(
id serial primary key,
name text,
funding_total numeric
);
insert into company values
(default, 'first_firm', 100),
(default, 'second_firm', 200);
drop table if exists acquisition;
create table acquisition(
id serial primary key,
acquiring_company_id int references company,
acquired_company_id int references company,
price_amount int
);
insert into acquisition values
(default, 1, 2, 50);
DROP TABLE
CREATE TABLE
INSERT 0 2
DROP TABLE
CREATE TABLE
INSERT 0 1
SELECT
a.acquiring_company_id,
a.acquired_company_id,
a.price_amount,
c1.funding_total,
c1.name as acquired_company_name,
c2.name as acquiring_company_name
FROM acquisition a
LEFT JOIN company c1
ON a.acquired_company_id = c1.id
LEFT JOIN company c2
ON a.acquiring_company_id = c2.id
WHERE price_amount <> 0 AND c1.funding_total <> 0
| acquiring_company_id | acquired_company_id | price_amount | funding_total | acquired_company_name | acquiring_company_name |
|---|---|---|---|---|---|
| 1 | 2 | 50 | 200 | second_firm | first_firm |
SELECT 1