I find that pretty often when working with data or fine-tuning a query, or updating some code that I need to compare 2 files. I sometimes use “File Merge” on Mac OS (it’s bundled with Xcode).
Or more recently I’ve been using https://www.diffchecker.com/
Give it a try and see the difference in 10 out of 3,435 rows of data from a query. See exactly what 2 variables changed in the new function someone wrote, etc….