RANKX function with ALL

You may refer at this tutorial

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Anonymous wrote:

Hi all,

 

I need your help on this please:

I have a Power BI model that contains the following two tables:
Sales(Sales_ID, sales_date, sales_amount, CustomerID)
Customer(CustomerID, First_name, Last_name)
There is a relationship between Sales and Customer.
I need to create a measure to rank the customers based on their total sales amount.

Which DAX formula should I use?

Is this the right formula: RANKX(ALL(customer), SUMX(RELATEDTABLE(Sales), [Sales_amount])) ?

 

Many thanks.

 

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I think correct ans is RANKX(ALL(Sales), SUMX(RELATEDTABLE(Customer), [Sales_amount])).

Bez question is asking to create a measure in Sales Table. Correct me If I am wrong?