| order_id | order_date | customer_id | invoice | | -------- | ---------- | ----------- | ------- | | 1 | 2020-09-15 | 1 | 30 | | 2 | 2020-09-17 | 2 | 90 | | 3 | 2020-10-06 | 3 | 20 | | 4 | 2020-10-20 | 3 | 21 | | 5 | 2020-11-10 | 1 | 10 | | 6 | 2020-11-21 | 2 | 15 | | 7 | 2020-12-01 | 4 | 55 | | 8 | 2020-12-03 | 4 | 77 | | 9 | 2021-01-07 | 3 | 31 | | 10 | 2021-01-15 | 2 | 20 |