登錄MySQL查看用SHOW VARIABLES LIKE ‘character%’;下字符集，顯示如下：
| character_set_client | utf8 |
| character_set_connection | utf8 |
| character_set_database | utf8 |
| character_set_filesystem | binary |
| character_set_results | utf8 |
| character_set_server | latin1 |
| character_set_system | utf8 |
| character_sets_dir | /usr/share/mysql/charsets/ |
解決方案：
1、在[client]字段里加入default-character-set=utf8
2、在[mysqld]字段里加入character-set-server=utf8
3、在[mysql]字段里加入default-character-set=utf8
修改完成後，service mysql restart重啓mysql服務就生效。注意：[mysqld]字段與[mysql]字段是有區別的。
最終結果如下：
[client]
port = 3306
socket = /var/run/mysqld/mysqld.sock
default-character-set=utf8
[mysqld_safe]
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
nice = 0
[mysqld]
user = mysql
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
port = 3306
basedir = /usr
datadir = /var/lib/mysql
tmpdir = /tmp
lc-messages-dir = /usr/share/mysql
explicit_defaults_for_timestamp
character-set-server=utf8
# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
bind-address = 127.0.0.1
log-error = /var/log/mysql/error.log
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
# * IMPORTANT: Additional settings that can override those from this file!
# The files must end with '.cnf', otherwise they'll be ignored.
#
!includedir /etc/mysql/conf.d/
[mysql]
no-auto-rehash
default-character-set=utf8
在丟失root密碼的時候，可以這樣
mysqld_safe --skip-grant-tables&
mysql -u root mysql
mysql> UPDATE user SET password=PASSWORD("new password") WHERE user='root';
mysql> FLUSH PRIVILEGES;
The server quit without updating PID file
只需要執行scripts/mysql_install_db --user=mysql
libaio.so.1: cannot open shared object file
執行sudo apt-get install libaio-dev
或
sudo apt-get install libaio1
utf8編碼設置在mysql/my.cnf中到[mysqld]下
[mysqld]
init_connect='SET collation_connection = utf8_unicode_ci'
init_connect='SET NAMES utf8'
character-set-server=utf8
collation-server=utf8_unicode_ci
skip-character-set-client-handshake