after the upgrade to MySQL 5.5 we've noted the strange bug which occurred on the default MySQL server config, it uses the utf16 collation as a default (at least it seems to me)
The strange behaviour is the following.
Create the table with the following two fields
CREATE TABLE `aa` ( `a` ENUM('on','off') NOT NULL DEFAULT 'off', `b` ENUM('on','off') NOT NULL DEFAULT 'off' ) CHARACTER SET 'utf16' COLLATE 'utf16_general_ci';
Dump the table and the structure will be the following
CREATE TABLE `aa` ( `a` ENUM('o','o') NOT NULL DEFAULT 'o', `b` ENUM('o','o') NOT NULL DEFAULT 'o' )ENGINE=InnoDB CHARACTER SET 'utf16' COLLATE 'utf16_general_ci';
Ubuntu 12.04.1 LTS Linux host 3.2.0-30-virtual #48-Ubuntu SMP Fri Aug 24 17:12:24 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux mysql-server-5.5 5.5.24-0ubuntu0.12.04.1 MySQL database server binaries and system database setup
Anybody can confirm this?
It seems NOT to happen with UTF8 collation, that can be forced to be a default in my.cnf
[mysqld] character-set-server = utf8 collation-server = utf8_unicode_ci init-connect='SET NAMES utf8' character-set-server = utf8