I made a web service that generates a data table that I periodically want to download into Excel. Because there is a huge amout of old data, I don't want to always generate everything - only data for dates which have not been downloaded yet.
If I last downloaded data into Excel two days ago, the next time I hit refresh, I want Excel to append the existing table, not replace the existing data with the new data. The web service is set up so that it will only generate data that has not previously been requested.
Is there a way to do this?