I have a MySQL table like this: +--------+-------+ + Server + Port + +--------+-------+ + 1 + 27001 + +--------+-------+ + 2 + 27002 + +--------+-------+ + 4 + 27004 + +--------+-------+ How you can see - here was 27003 port - but it was deleted some time ago (just for example). Is there some way to know the minimum value that is not used (higher than 27000 for example) in mysql table? Or there is no way and I need to make an separate table with all ports and column with "used" or "not used" ? Situation explanation: I am creating game hosting website, and I can use auto-increment for ports, but I will have a lot of deleted/unused ports after some time, and I want to use all of them before increasing port range. Thanks for your answers!