mysql: unknown variable 'character-set-client=utf8'_MySQL
在同事安装的MySQL服务器上(居然安装的是My-SQL 5.1.73的老旧版本),登录MySQL时遇到下面“mysql: unknown variable 'character-set-client=utf8'”错误:
[root@MySQLDB002 lib]# mysql -u root -p
mysql: unknown variable 'character-set-client=utf8'
检查MySQL的配置文件/etc/my.cnf发现
[root@MySQLDB002 lib]# more /etc/my.cnf [mysqld] datadir=/var/lib/mysql socket=/var/lib/mysql/mysql.sock user=mysql # Disabling symbolic-links is recommended to prevent assorted security risks symbolic-links=0 default-character-set=utf8 character-set-server=utf8 [client] default-character-set=utf8 character-set-client=utf8 [mysql] default-character-set=utf8 [mysqld_safe] log-error=/var/log/mysqld.log pid-file=/var/run/mysqld/mysqld.pid
网上有资料说这个是mysqlbinlog的一个bug,但是搜索外文资料并没有搜索到相关信息,虽然还是并没有彻底弄明白原因,但是不妨自己验证了一下下面几种解决方面
解决方法1:屏蔽character-set-client=utf8,此时连接MySQL语句没有问题。
解决方法2:使用loose-default-character-set=utf8 loose-选项,loose为宽松的, 散漫的, 自由的意思,在选项前加了loose-,则当程序不认识此选项时会略过此选项,并给出一个警告。测试亦可解决问题。

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