SELECT 
    p.name,
    v.default_sell_price - v.default_purchase_price as margin,
    ((v.default_sell_price - v.default_purchase_price)/v.default_purchase_price * 100) as margin_percentage
FROM products p
JOIN variations v ON p.id = v.product_id
WHERE v.default_purchase_price > 0
ORDER BY margin_percentage DESC
LIMIT 10;