Not Just Customer Data,
Actionable Insights

WITH monthly_sales AS (
    SELECT 
        DATE_TRUNC('month', s.purchase_date) AS purchase_month,
        s.sales_channel,
        SUM(s.total_amount_usd) AS total_sales
    FROM sales s
    WHERE s.purchase_date IS NOT NULL
    GROUP BY DATE_TRUNC('month', s.purchase_date), s.sales_channel
)
SELECT 
    purchase_month,
    sales_channel,
    total_sales
FROM monthly_sales
WHERE total_sales IS NOT NULL
ORDER BY 
    purchase_month ASC NULLS LAST,
    sales_channel ASC;