Pandas assign to SELECT list expressions

New columns are expressions. They do not persist unless you ALTER TABLE or SELECT INTO.

SELECT order_id,
       total_amount * 1.0 AS gbp,
       CONVERT(char(7), order_date, 120) AS ym
FROM Orders;

Chained assign is more columns, still one SELECT.

Canonical translation

SELECT order_id,
       total_amount * 1.0 AS gbp,
       CONVERT(char(7), order_date, 120) AS ym
FROM Orders;