跳过授权表登录后使用insert into创建root权限用户

起因：
刚刚搭建好的mysql数据库，做基础优化时，不小心把所有用户都删除了，并且退出了。没办法，只好跳过授权表登录，新建root用户。
过程如下：

一、停掉mysql，跳过授权登录
[root@explnk-zabbix zabbix-2.2.9]# /etc/init.d/mysqld stop
Shutting down MySQL... SUCCESS!
[root@explnk-zabbix zabbix-2.2.9]# mysqld_safe --skip-grant-table &
[1] 30178
[root@explnk-zabbix zabbix-2.2.9]# 160418 10:49:54 mysqld_safe Logging to '/application/mysql/data/explnk-zabbix.err'.
160418 10:49:54 mysqld_safe Starting mysqld daemon with databases from /application/mysql/data

[root@explnk-zabbix zabbix-2.2.9]# mysql
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.32 MySQL Community Server (GPL)

Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

二、创建拥有root权限的用户
2.1 错误例子：
这里最开始遇到个坑，使用insert into创建的用户没有任何权限，登录之后无法进行操作，语句如下：
INSERT INTO user (Host,User,Password) VALUES('localhost','root',PASSWORD('biscuit'));

*************************** 2. row ***************************
Host: localhost
User: root
Password: *7495041D24E489A0096DCFA036B166446FDDD992
Select_priv: N
Insert_priv: N
Update_priv: N
Delete_priv: N
Create_priv: N
Drop_priv: N
Reload_priv: N
Shutdown_priv: N
Process_priv: N
File_priv: N
Grant_priv: N
References_priv: N
Index_priv: N
Alter_priv: N
Show_db_priv: N
Super_priv: N
Create_tmp_table_priv: N
Lock_tables_priv: N
Execute_priv: N
Repl_slave_priv: N
Repl_client_priv: N
Create_view_priv: N
Show_view_priv: N
Create_routine_priv: N
Alter_routine_priv: N
Create_user_priv: N
Event_priv: N
Trigger_priv: N
Create_tablespace_priv: N
ssl_type:
ssl_cipher:
x509_issuer:
x509_subject:
max_questions: 0
max_updates: 0
max_connections: 0
max_user_connections: 0
plugin:
authentication_string: NULL

2.2 正确方法1：
mysql> use mysql
Database changed
mysql> insert into user (Select_priv, Insert_priv, Update_priv, Delete_priv, Create_priv, Drop_priv, Reload_priv, Shutdown_priv, Process_priv, File_priv, Grant_priv, References_priv, Index_priv, Alter_priv, Show_db_priv, Super_priv, Create_tmp_table_priv, Lock_tables_priv, Execute_priv, Repl_slave_priv, Repl_client_priv, Create_view_priv, Show_view_priv, Create_routine_priv, Alter_routine_priv, Create_user_priv, Event_priv, Trigger_priv,Create_tablespace_priv,User,Password) values ( 'Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','Y','gl','gl');
Query OK, 1 row affected, 3 warnings (0.06 sec)

mysql> update user set password=PASSWORD('explink') where user='gl';
Query OK, 1 row affected (0.08 sec)
Rows matched: 1 Changed: 1 Warnings: 0

2.3 正确方法2：
跳过授权表登录后是无法使用grant建立用户的，报错如下：
mysql> grant all privileges on *.* to liang@'localhost' identified by '123456' with grant option;
ERROR 1290 (HY000): The MySQL server is running with the --skip-grant-tables option so it cannot execute this statement

解决办法：
只要刷新一下用户权限即可
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

mysql> grant all privileges on *.* to liang@'localhost' identified by '123456' with grant option;
Query OK, 0 rows affected (0.00 sec)

三、退出登录并重新启动mysql
[root@explnk-zabbix zabbix-2.2.9]# /etc/init.d/mysqld stop
[root@explnk-zabbix zabbix-2.2.9]# /etc/init.d/mysqld start

四、登录mysql查看权限

[root@explnk-zabbix zabbix-2.2.9]# mysql -ugl -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.32 MySQL Community Server (GPL)

Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> select * from mysql.user\G

*************************** 3. row ***************************
Host:
User: gl
Password: *5F70B50879BD3B98CB5A945D3A6A7C92F41B8AE8
Select_priv: Y
Insert_priv: Y
Update_priv: Y
Delete_priv: Y
Create_priv: Y
Drop_priv: Y
Reload_priv: Y
Shutdown_priv: Y
Process_priv: Y
File_priv: Y
Grant_priv: Y
References_priv: Y
Index_priv: Y
Alter_priv: Y
Show_db_priv: Y
Super_priv: Y
Create_tmp_table_priv: Y
Lock_tables_priv: Y
Execute_priv: Y
Repl_slave_priv: Y
Repl_client_priv: Y
Create_view_priv: Y
Show_view_priv: Y
Create_routine_priv: Y
Alter_routine_priv: Y
Create_user_priv: Y
Event_priv: Y
Trigger_priv: Y
Create_tablespace_priv: Y
ssl_type:
ssl_cipher:
x509_issuer:
x509_subject:
max_questions: 0
max_updates: 0
max_connections: 0
max_user_connections: 0
plugin:
authentication_string: NULL
3 rows in set (0.00 sec)

六、perfect

参考blog：http://my.oschina.net/leejun2005/blog/76140
本文出自 “阴晴圆缺” 博客，请务必保留此出处http://gouliang.blog.51cto.com/10735353/1764976