Does auto increment start again at 0 if max value reached?

auto-increment, max, mysql, reset

Solution

The documentation is pretty clear on what happens:

When the column reaches the upper limit of the data type, the next attempt to generate a sequence number fails.

Read about it here.

So the answer to your question is "no". It generates an error.

Problem

Does MySQL's auto increment reset to `0` after reaching the maximum value? In other words, if an `UNSIGNED SMALLINT` column with `AUTO_INCREMENT` reaches `65535` what happens on a new `INSERT`? If there are no available values, what happens then?

Original source