WITH RecentOrders AS (
  SELECT order_id, user_id, order_date
  FROM orders
  WHERE order_date >= '2023-10-01'
),
UserOrderCounts AS (
  SELECT user_id, COUNT(order_id) AS total_orders
  FROM RecentOrders
  GROUP BY user_id
)
SELECT u.username, uoc.total_orders
FROM users u
JOIN UserOrderCounts uoc ON u.user_id = uoc.user_id
ORDER BY uoc.total_orders DESC;