SELECT
	category,
    name,
    date_upd :: date,
    MAX(price) - MIN(price) AS max_min_diff
FROM
	products_data_all
WHERE
	category = 'масло сливочное и маргарин' AND date_upd BETWEEN '2019-06-09' AND '2019-06-11'
GROUP BY
    category,
    name,
    date_upd;