10.1.6 Character Set for Error Messages

This section describes how the server uses character sets for constructing error messages and returning them to clients. For information about the language of error messages (rather than the character set), see Section 10.2, “Setting the Error Message Language”.

In MySQL, the server constructs error messages and returns them to clients as follows:

The preceding method of error-message construction can result in messages that contain a mix of character sets unless all items involved contain only ASCII characters. This issue is resolved in MySQL 5.5, in which error messages are constructed internally within the server using UTF-8 and returned to the client in the character set specified by the character_set_results system variable.