Custom column calculation

[notski]

Hey folks,

I'm fairly new to Power BI so I appreciate all the help I can get 🙂

I have two tables, one with a sales ledger (Sales) and the other containing product information (Products). Each row on Sales details the Date, Item Number, Sales Amount, Sales Quantity and Cost Amount, and the rows in Products contain Item Number and Unit Cost (among other things).

Due to issues with the ERP I'm working with, Cost Amounts for some transactions on the Sales table are outrageously wrong and can't be corrected in the source data, so I need to calculate a corrected cost amount for transactions which meet a certain criteria (let's assume Sales Amount - Cost Amount < 0). For transactions meeting the criteria, I need to fetch the Unit Cost from the Products table and multiply that by Sales Quantity. Transactions which don't meet the criteria should be left as they are.

What would be the best way to go about this? My initial idea was to create a custom column (let's call it Corrected Cost) on the Sales table which evaluates the criteria and either calculates a new cost or inputs the existing Cost Amount. I'm just not sure how to make it happen 😄

Thanks in advance!

[Greg_Deckler · Accepted solution]

The exact details are going to depend on your data. But, let's say that Sales and Product tables are related on ProductID. You could do something like this:

Column = IF(([Sale Amount]-[Cost Amount])>0,[Sale Amount],RELATED('Products'[Price]))

Something along those lines.