Customers With Increasing Orders

Return the customer_ids whose order amounts strictly increase every time they order (ordered by order_date). Customers with a single order qualify.

Table schema

Orders(id INT PRIMARY KEY, customer_id INT, order_date DATE, amount INT)

Sample data

id | customer_id | order_date | amount
1 | 1 | 2026-01-01 | 10
2 | 1 | 2026-02-01 | 20
3 | 2 | 2026-01-01 | 30
4 | 2 | 2026-02-01 | 25
5 | 3 | 2026-01-01 | 5