Populating Excel Table with New Data from CSV -- Help

[powerappspro1]

I have an excel sheet with a table that holds data. I have a query that runs every day that populates a CSV file with updated data. The table and CSV file are the same, with the exception of new rows on the CSV file representing new entries. How can I compare the CSV file and Excel table and only add the new rows to the excel table?

The only way I could figure out was to wipe the entire excel table and repopulate the data daily, but that is not efficient. Attached are screenshots of the current flow. Thanks!

[takolota · Accepted solution]

You can use a Select to get all the unique primary key values from the Excel table. You will need to insert the Excel values output into the From input, switch the right-side Map toggle to a single input, & insert in that single Map input something like

item()?['InsertPrimaryKeyColumnName']

Then follow that with a Filter array on the JSON of the CSV data, use in the condition…

Select Body Output does not contain CSV unique primary key value, like

item()?['InsertCSVPrimarKeyColumnName']

That will filter everything down to the rows in the CSV not found in the Excel table so you can then add them to the Excel table.

[powerappspro1]

I understand that would be the solution in theory, but whenever I try to do that I end up with endless "Apply to each" loops that do not return the desired output. I'm not sure how to structure those kind of select and filter functions given the "apply to each" loops. 

[powerappspro1]

nevermind - figured it out

[jrod82]

How did you end up solving this? I am having similar issues and am stuck in hell it seems lol

https://powerusers.microsoft.com/t5/Building-Flows/Flow-to-download-csv-attachment-to-OneDrive-and-p...

[takolota]

@jrod82 

I updated the solution post to provide more details