Save XLSX to Data Table

I think you are trying to store the entirely already created excel file in a database row?

I do this all the time, you are very close, you just need to turn your file into a media object to store in the data table like:

import anvil.media

excel_media_object = anvil.media.from_file(filename, name=filename)

app_tables.worksheets.add_row(
                                created=datetime.now(),
                                name=name, 
                                worksheet=excel_media_object
                                   )

Are you doing this on your own system using anvil-uplink? Before I moved to a paid plan I used the uplink for things like using openpyxl since it was not available using the free plan in server modules.

If you are using uplink, this should just work.