Postgres 15

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select @@version;

ERROR:  column "version" does not exist
LINE 1: select @@version;
                 ^

create table boxes
(
    id   bigserial primary key,
    name varchar(255)
);

create table animals
(
    id     bigserial primary key,
    name   varchar(255),
    age    numeric,
    box_id bigint constraint animals_boxes_id references boxes
);

create table vegetables
(
    id     bigserial primary key,
    name   varchar(255),
    weight numeric,
    box_id bigint constraint vegatables_box_id references boxes
);

insert into boxes (name) values ('First box');
insert into animals (box_id, name, age) values (1, 'Cat', 2);
insert into animals (box_id, name, age) values (1, 'Cat', 3);
insert into animals (box_id, name, age) values (1, 'Dog', 5);
insert into vegetables (box_id, name, weight) values (1, 'Tomato', 20);
insert into vegetables (box_id, name, weight) values (1, 'Cucumber', 30);
insert into vegetables (box_id, name, weight) values (1, 'Potato', 50);

CREATE TABLE

CREATE TABLE

CREATE TABLE

INSERT 0 1

INSERT 0 1

INSERT 0 1

INSERT 0 1

INSERT 0 1

INSERT 0 1

INSERT 0 1

select b.name                                 as box_name,
       string_agg(a.name, ', ' order by a.id) as animal_names,
  string_agg(v.name, ', ' order by v.id) as vegetable_names
from boxes as b
         left join animals a on b.id = a.box_id
  left join vegetables v on v.id = a.id
group by b.name;

box_name
animal_names
vegetable_names

First box
Cat, Cat, Dog
Tomato, Cucumber, Potato

SELECT 1