Calculating Non First Order Of the customer

Dear Experts

Please refer to this topic tutorial link: https://towardsdatascience.com/explore-the-potential-of-products-through-customers-purchase-behaviour-in-power-bi-basket-a1f77e8a2bf6

Please refer to this topic tutorial link: https://towardsdatascience.com/explore-the-potential-of-products-through-customers-purchase-behaviour-in-power-bi-basket-a1f77e8a2bf6

My question is regard the calculated column (IsFirstorder) as it said in the page :
" First, classify all orders for the sales table, in all orders of the customer, one or more orders with the earliest order date are classified as the first order, the rest are “non-first”:" , when I implemented it on my showcase it gives me (out of memory problem) this happen when I call the measure (CustPurchaseOthersSubcategoryAfter ) as on this image:

because the table I’m using it is above 10M rows not like the one used on the (Page tutorial) , Is there any alternatives such as :
1- Using custom column in Query editor?
Or
2-Using measure ,
or any other suggestion to avoid the out of memory and/or bad performance ?