Looking up the correct value from a table with values per periods, based on a unique date

[Brandaris]

Hello,,

I have the following challenge that I hope you can help me with:

In table "Orders" I have:

- customer ID
- product ID
- order date (dates from 1-1-2019 to 1-3-2021)
- quantity
- amount

In the table "COSTPRICES" I have at least 3 different cost prices for each Product ID depending on the date.

For example:

Row 1 the cost price from 1-1-2019 to 1-11-2019;

Row 2 is the costprice from 11/2/2019 to 7/6/2020 and

Row 3 is the costprice from 6/7/2020 until now.

The column headings are:
- product ID
- start date
- end date
- cost price

NB: There's also a calendar table in the PBIX

Now I want to get the correct cost price per order from the cost price table and add it to the order table. That has to be the unique cost price that belongs to the order date and that must match just one of the 3 periods in which this cost price is determined. The LOOKUPVALUE function is obviously not an option, as it does not reference a unique value.

What is the best approach to this question?

Thank you very much for your help!

Sincerely,
Hans

[AlB · Accepted solution]

Hi @Brandaris 

Create a calculated column in the Orders table:

Price =
CALCULATE (
    DISTINCT ( CostPrices[Cost price] ),
    FILTER (
        ALL ( CostPrices[product ID], CostPrices[start date], CostPrices[end date] ),
        CostPrices[product ID] = Orders[product ID]
            && CostPrices[start date] <= Orders[date]
            && CostPrices[end date] > Orders[date]
    )
)

Please accept the solution when done and consider giving a thumbs up if posts are helpful.  Contact me privately for support with any larger-scale BI needs, tutoring, etc.

[Brandaris]

Dear AIB,

Thank you very much for your quick and super good solution!

To let this solution work correctly, there must be no relationship between the calendar table and the cost price table (containing 2 date columns). Between the order table (with 1 date column) and the calendar table, of course, and fortunately yes ;-).

Instead of the DISTINCT function, I also tried the VALUES function. That works well too.