SELECT
	name,
	CASE
        WHEN weight IS NULL AND units = '%'  THEN 72
        WHEN weight IS NULL AND units = 'кг' THEN 1
        WHEN weight IS NULL AND units = 'л' THEN 1
        WHEN weight IS NULL AND units = 'мл' THEN 805
        WHEN weight IS NULL AND units = 'г' THEN 402
        ELSE weight END AS weight_info
FROM
	products;