Add a new file to Source.Files with 4 additional columns previous files don't have

[castanheiro1982]

Hi team,

I am having trouble with this:

I have 13 CSV files as my power BI data source, growing on a weekly basis, but now i have 4 additional columns. How do i tell power BI that he should have let's say these 4 columns to the full dataset and populate the previous files with let's say null values.

thanks,

[MFelix · Accepted solution]

Hi @castanheiro1982

The best option for this is to change the file that you use as your transformation file, that way when you append the files using the custom function the columns will be filled with null.

You just need to edit the step Navigation on the Sample File:

• Go to the Sample file
• Source
• Check the number of the line of the new file you want to use as new default file
• On the navigation step change the 0 by the line number -1 that you took on the previous point
  • If line is 35 you should place 34

= Source{0}[Content]

• • Go to the Transform Sample file and make the necessary changes.
  • On the query file you should have the previous file with null on the additional columns

[castanheiro1982]

Thank you Miguel!

that did the job very easily and now I learned a new option 🙂