It's wonderful to see posts like this. I've been often very frustrated by exactly similar issues. But this seems to be much more common than I thought. One guy

It's wonderful to see posts like this. I've been often very frustrated by exactly similar issues. But this seems to be much more common than I thought. One guy used select max(id) from table; for over 5gb table without id column index, periodically. It took quite a while every time maxing the disk I/O. Usually developers claim that the server doesn't have enough memory or it should jave more cores and we should buy enterprise SSDs. Which is simply insane when you could fix the issue very easily.