I have a large dataset stored in Google Sheets, but because of performance issues, I had to break it into two different files.

Both files have the same exact column headers and value types per column; the only difference is File A contains data for 2016 Q4 - 2017 Q2, and File B contains data for 2013 Q2 - 2016 Q3. What would be the best way to go about combining these two files so that my visualizations show everything from 2013 Q2 - 2017 Q2?

It doesn't look like I can do cross-database Unions, so I guess it would be a join? But someone else told me I should just work off an extract but I'm unclear on how that would work.

Any help is much appreciated.