Comment by MooMooMilkParty

You're blowing my mind here a little bit. I don't use MySQL but do use Excel and the R/Python data science stacks quite a bit. I regularly open data with tens or even hundreds of thousands of columns in the latter by using lazy computations. Is this not the case with database approaches? What kind of hardware are we talking? Presumably Excel has to load everything into memory at once since it's immediately viewable, right?