How does a database handle auto-number field if it's limit is reached?

Question

Hello,

In my tables, i have selected id column to be of type int (4 bytes). The answer i want to know is how will any database handle it once it's limits are reached? Will the database refuse to insert any more records in table? or what exactly will happen? Also how should i tackle this type of problem (if the database doesn't handle it by itself)?

Answer 1

I would love to know what you refer to as "the" database. But usually it is an error. The database is full then. You should provide some means for "compacting" the primary key then, or more easy:

Use long integers as keys (8 bytes). Even if you insert 1000 items per second from now on, this will last for nearly 300 million years. The 4 byte integer (signed) will only last for 24 days in this scenario.