auto increment - What happens when auto_increment on integer column reaches the max_value in databases?

Question

I am implementing a database application and I will use both JavaDB and MySQL as database. I have an ID column in my tables that has integer as type and I use the databases auto_increment-function for the value.

But what happens when I get more than 2 (or 4) billion posts and integer is not enough? Is the integer overflowed and continues or is an exception thrown that I can handle?

Yes, I could change to long as datatype, but how do I check when that is needed? And I think there is problem with getting the last_inserted_id()-functions if I use long as datatype for the ID-column.

Answer 1

Jim Martin's comment from §3.6.9. "Using AUTO_INCREMENT" of the MySQL documentation:

Just in case there's any question, the AUTO_INCREMENT field /DOES NOT WRAP/. Once you hit the limit for the field size, INSERTs generate an error. (As per Jeremy Cole)

A quick test with MySQL 5.1.45 results in an error of:

ERROR 1467 (HY000): Failed to read auto-increment value from storage engine

You could test for that error on insert and take appropriate action.