Filter Aggregated Groups with HAVING Clause in SQL

Question

From `orders`, find all `customer_id`s who have placed at least 5 orders AND whose total spend exceeds $10,000.

Accepted Answer

Optimal Solution:
SELECT 
  customer_id,
  COUNT(order_id) AS order_count,
  SUM(amount) AS total_spend
FROM orders
GROUP BY customer_id
HAVING COUNT(order_id) >= 5
   AND SUM(amount) > 10000
ORDER BY total_spend DESC;

Technical Explanation:
`WHERE` filters rows before grouping; `HAVING` filters aggregated buckets after `GROUP BY` has collapsed rows.

order_id	customer_id	amount
1	101	3000
2	101	3000
3	101	2500
4	101	1500
5	101	500
6	102	12000