DBOLT

SELECT p.product_name,
       SUM(l.quantity) AS units_sold,
       SUM(l.line_total) AS revenue,
       SUM(l.quantity * c.unit_cost) AS cost,
       SUM(l.line_total
           - l.quantity * c.unit_cost) AS profit
FROM demo_invoice_lines l
JOIN demo_products p ON p.id = l.product_id
JOIN demo_costs c ON c.product_id = p.id
WHERE l.invoice_date >= DATE '2026-01-01'
GROUP BY p.product_name
ORDER BY profit DESC;