Why Does My InnoDB Auto-Increment Counter Keep Incrementing Despite Duplicate Keys?

InnoDB Auto-Increment Increment Issue on Duplicate Keys

In an InnoDB database table with a primary key set to auto-increment, it is observed that the auto-increment counter continues to increment even when duplicate keys are detected. This behavior leads to non-consecutive IDs, as demonstrated in the provided example. To resolve this issue, consider implementing the following solution:

Modifying the MySQL Configuration

By setting the innodb_autoinc_lock_mode configuration option to "0", you can switch to the traditional auto-increment lock mode. This mode ensures that all INSERT statements will assign consecutive values to auto-increment columns, even when attempting to insert duplicate keys.

SET GLOBAL innodb_autoinc_lock_mode = 0;

It is important to note that consecutive IDs should not be relied upon for any application logic. Their primary purpose is to provide unique identifiers for each record. While consecutive IDs may be aesthetically pleasing, they do not offer any practical benefits and can potentially lead to issues in distributed systems.

The above is the detailed content of Why Does My InnoDB Auto-Increment Counter Keep Incrementing Despite Duplicate Keys?. For more information, please follow other related articles on the PHP Chinese website!