CREATE TABLE furniture (
type varchar(64),
model varchar(64)
);
INSERT INTO furniture VALUES
('Кухня', 'Акация'),
('Кухня', 'Пальма'),
('Кухня', 'Тополь'),
('Кухня', 'Дуб'),
('Прихожая', 'Ромашка'),
('Прихожая', 'Ландыш');
SELECT type, JSON_ARRAYAGG(model) AS models
FROM furniture
GROUP BY type;