Aikesheng Open Source Community
Jun 11, 2025 · Databases
Why Does Adding a Column Trigger Duplicate Entry Errors in MySQL?
An experienced DBA explains why adding a new column in MySQL can unexpectedly raise duplicate entry errors during online DDL, detailing the role of primary and unique keys, the innodb_online_alter_log_max_size setting, and how concurrent DML operations cause the conflict.
DDLMySQLdatabase
0 likes · 8 min read