Power Bi Power Query best practice

Question

I have a large volume of CSV data that is imported and transformed, one of the columns has a range of values from 1-19, and is an age-group identifier (0-4,5-9,10-14,...,80-84,85+,age unknown).

My questions is

"Is it best to add DAX code (likely a switch command) to make 1 = 0-4, 2 = 5-9,..., or is it better to do this in a different manner?"

I know how to accomplish this in the import/transform data area, I'm looking for a better practice to consider.

"If there is a better practice, can you please describe why the other method is deficient and the proposed better?"

Answer 1

PowerBI already has some in-built support that allows you to group multiple numeric values together called "Grouping" and "Binning" . You can probably use that.

But wrt best practice is think you need to compare the three approaches and see what works best for you

1. "Grouping" or "Binning" - PowerBI takes care of it for you, but it may not be exactly what you're looking for.
2. DAX - this could impact the performance of the visual interactivity or loading
3. Power Query - This will simplify the performance with visuals, but will add time to make this transformation on every refresh.

What works for you will depend on what you're ready to accept.