Since manually scrolling through 10M rows is not likely... at that point isn't it better to just use an SQL DB rather than a spreadsheet?
SQlite could be enough, and it's comparable to a spreadsheet in that it is well suited to a single-file single-user local-DB scenario, yet can still handle large quantities of data.
SQlite could be enough, and it's comparable to a spreadsheet in that it is well suited to a single-file single-user local-DB scenario, yet can still handle large quantities of data.