By default, mysqld produces error messages in English, but they can also be displayed in any of several other languages: Czech, Danish, Dutch, Estonian, French, German, Greek, Hungarian, Italian, Japanese, Korean, Norwegian, Norwegian-ny, Polish, Portuguese, Romanian, Russian, Slovak, Spanish, or Swedish.
You can select which language the server uses for error messages using the instructions in this section.
As of MySQL 5.5, the server searches for the error message file in two locations:
It tries to find the file in a directory constructed from two parts, the value of
--lc-messages-dirand the value of--lc-messagesconverted to a language name. Suppose that you start the server using this command:shell>
mysqld --lc-messages-dir=/usr/share/mysql --lc-messages=fr_FRIn this case, mysqld maps the locale
fr_FRto the languagefrenchand looks for the error file in the/usr/share/mysql/frenchdirectory.If the message file cannot be found in the directory constructed as just described, the server ignores the
--lc-messagesvalue and uses only the--lc-messages-dirvalue as the location in which to look.
The --lc-messages-dir and
--lc-messages options are
accompanied by the
lc_messages_dir and
lc_messages system variables.
lc_messages_dir has only a global
value and is read only.
lc_messages has global and
session values and can be modified at runtime, so the error
message language can be changed while the server is running, and
individual clients each can have a different error message
language by changing their session
lc_messages value to a different
locale name. For example, if the server is using the
fr_FR locale for error messages, a client that
wants error messages in English can execute this statement:
mysql> SET lc_messages = 'en_US';
Before MySQL 5.5, the
--lc-messages-dir and
--lc-messages options (and
accompanying system variables) were unavailable. To start
mysqld with a particular language for error
messages, the --language or
-L option were used. The option value can be a
language name or the full path to the error message file. For
example:
shell> mysqld --language=swedish
Or:
shell> mysqld --language=/usr/local/share/swedish
The language name should be specified in lowercase.
From MySQL 5.5 on, --language is
treated as an alias for
--lc-messages-dir.
By default, the language files are located in the
share/mysql/
directory under the MySQL base directory.
LANGUAGE
For information about changing the character set for error messages (rather than the language), see Section 9.1.6, “Character Set for Error Messages”.
You can change the content of the error messages produced by the server using the instructions in the MySQL Internals manual, available at http://forge.mysql.com/wiki/MySQL_Internals_Error_Messages. If you do change the content of error messages, remember to repeat your changes after each upgrade to a newer version of MySQL.