Window Functions

-- snippets/window-functions/code-postgres.sql
-- Platzhalter-Code für Window Functions in PostgreSQL
SELECT
    customer_id,
    order_id,
    order_date,
    SUM(order_amount) OVER (
        PARTITION BY customer_id
        ORDER BY order_date
        ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
    ) AS running_total
FROM orders;