[hans_castorp]

I have seen a lot of people sort by (generated) integer values to return the rows "in creation order" assuming that sorting by an integer is somehow magically faster than sorting by a proper timestamp value (which give a more robust "creation order" sorting than a generated integer value).

[sgarland]

Assuming the integer value is the PK, it can in fact be much faster for MySQL / MariaDB due to InnoDB’s clustering index. If it can do a range scan over the PK, and that’s also the ORDER BY (with matching direction), congratulations, the rows are already ordered, no sort required. If it has to do a secondary index lookup to find the rows, this is not guaranteed.