Pandas reset_index — usually nothing in SQL

The index is a pandas habit. GROUP BY keys are already columns. You do not reset them.

SELECT customer_id, SUM(total_amount) AS sales
FROM Orders
GROUP BY customer_id;

A row number column is ROW_NUMBER() OVER (ORDER BY ...), not an index.

Canonical translation

SELECT customer_id, SUM(total_amount) AS sales
FROM Orders
GROUP BY customer_id;