Data Missing in Power Query

[ChrisJ31]

We're essentially using Power BI to join data from several Excel files only to export the joined data as another Excel file. One query used in our tool combines and transforms about 25 Excel files from a single folder. All of these files have the same structure and are formatted similarly. We recently noticed that data from one of the columns from one of the Excel files is missing (showing as null/blank). Oddly enough, this issue surfaced only a couple days ago after several weeks of using the tool without issue. What's even more strange is that the header/filter row of this column in the Excel file is carried over and retained without issue. To my knowledge, no changes have been made to the structure of the affected Excel file, nor has the data changed in a drastic way.

[jennratten · Accepted solution]

Hello - Power BI does not modify source files, so if something has changed with the output there was either a change to the source file or the script.  For the file that is missing a column, I recommend you first check the file properties in the folder for the created date and modified date to confirm that the file really was not modified or replaced.  Also open up the file to see if the column is really present and has the expected column name.  If it has not been modified/replaced, go to the script.  Check to see if how the files are being transformed and combined to get to the result.  Click each step of the Power Query steps and view the result to see which step is impacting your result.

[ChrisJ31]

Thanks for the feedback! It looks like the header for that column was updated at some point (one letter was capitalized that wasn't capitalized in our sample file used in Power BI).

[jennratten]

You're welcome!