SQLite vs Excel for STD as database

I generated 360k orders yesterday and I tested it today using XLS as the database… It did not go well. So I put together a quick test “rig” to see how it would compare against the simple SQLite database. You do not need to guess what the outcome was.

Now… in the long run would I still use Excel as the medium that new data will be imported in bulk via some kind of scheduled task or I use csv file for that? I guess that would depend on how many tables/sheet you have to manage.