Average order value by channel

Data

Download the practice file(s):

Steps

1. Join order_items to orders on order_id.
2. Filter to 2025 orders.
3. GROUP BY o.channel.
4. Compute SUM(net sales) / COUNT(DISTINCT o.order_id). Use COUNT(DISTINCT) because one order has several lines.
5. Compare both channels, then read the Online row.

SELECT o.channel,
       ROUND(SUM(oi.quantity * oi.unit_price * (1 - oi.discount))
             / COUNT(DISTINCT o.order_id), 2) AS aov
FROM order_items oi
JOIN orders o ON o.order_id = oi.order_id
WHERE o.order_date BETWEEN '2025-01-01' AND '2025-12-31'
  AND o.channel = 'Online'
GROUP BY o.channel;