Средняя логистика на единицу товара по каналам за последний месяц
SQL, по которому посчитано
WITH period AS (
SELECT CAST(date_trunc('month', max(date)) AS DATE) AS month_start
FROM sales
)
SELECT
channel,
round(SUM(logistics) / NULLIF(SUM(units), 0), 2) AS logistics_per_unit
FROM sales
CROSS JOIN period
WHERE date >= period.month_start
GROUP BY channel
HAVING SUM(units) > 0
ORDER BY logistics_per_unit DESC