Count Unique Values Conditionally -Code

Hi,

I have a table that looks like that :

Untitled.png

I 'd need a macro that would summarize the sales person's name, number of orders and revenue:

Untitled2.png

my problem is that I don't know how to handle orders because each item on the order is listed on a separate line and I need to count unique orders for each sales person separately


I know that there is a way to do this with an array formula, but i am really simplifying my data- in reality it's 30 thousand records which would take a long time to recalculate

Thanks!