I have a table that is exposed to large inserts and deletes on a regular basis (and because of this there are large gaps in the number sequence of the primary id column). It
I know it has been already answered a year ago but just to continue on Luc Franken answer,
If you insert 500 million rows per second, it would take around 1173 years to reach the limit of the BIG INT. So yeah i think don't worry about that