In MariaDB 5.5.28 (and merged into 10.0.0) the following change was made by Monty:

http://bazaar.launchpad.net/~maria-captains/maria/10.0-base/revision/3413.16.2#sql/sql_insert.cc

This causes warnings to be emitted by INSERT IGNORE, which differs from MySQL behavior and specifically contradicts the documentation for INSERT IGNORE which says:

http://dev.mysql.com/doc/refman/5.5/en/insert.html

"If you use the IGNORE keyword, errors that occur while executing the INSERT statement are ignored. For example, without IGNORE, a row that duplicates an existing UNIQUE index or PRIMARY KEY value in the table causes a duplicate-key error and the statement is aborted. With IGNORE, the row still is not inserted, but no error occurs. Ignored errors may generate warnings instead, although duplicate-key errors do not."

The MariaDB page on IGNORE doesn't mention this difference:

https://mariadb.com/kb/en/ignore/

This new behavior is not actually desired and causes incompatibilities in some cases (e.g. clients who use INSERT IGNORE and actually check warnings). This should have been gated behind a SQL_MODE at least.

Is there any chance this change could be reverted or corrected?