SQL Windowing functions: does the order of appearance for columns matter in partition by?

Question

I'm trying to better understand the analytical functions in SQL.

1. Is my understanding correct that the windowing function will be applied to every unique combination of fields that appear in "partition by"?

2. If I were to partition my result-set by several fields, does the order of appearance of these fields matter?

To be more specific, would the results of the following two queries differ in any circumstances?

Select customer_code,
       state,
       weekOfDate, 
       SUM(Sales) over(partition by customer_code,state,weekOfDate)
From Sales

Select customer_code,
       state,
       weekOfDate, 
       SUM(Sales) over(partition by weekOfDate,state,customer_code)
From Sales

Answer 1

#1: yes

#2: no

PARTITION BY is similar to GROUP BY, ORDER doesn't matter