SELECT '{"wrap": "подарочная", "notes": ["позвонить заранее"], "urgent": true}'::jsonb AS wishes;

SELECT w->>'wrap' AS wrap, w->'notes'->>0 AS first_note, (w->>'urgent')::boolean AS urgent
FROM (SELECT '{"wrap": "подарочная", "notes": ["позвонить заранее"], "urgent": true}'::jsonb AS w) AS t;

SELECT jsonb_build_object('id', id, 'name', name, 'price', price) AS item
FROM products
LIMIT 3;

SELECT c.name AS category, jsonb_agg(p.name ORDER BY p.name) AS items
FROM categories c
JOIN products p ON p.category_id = c.id
GROUP BY c.name;