删除用户
删除用户
mysql> truncate mysql.user;
Query OK, 0 rows affected (0.05 sec)
mysql> select user,host from mysql.user;
Empty set (0.00 sec)
重启mysql服务并登录
[root@db01 ~]# systemctl restart mysqld
[root@db01 ~]# mysql
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
#登录错误
恢复用户
当登录不上去首先停掉正在运行的数据库
[root@db01 ~]# systemctl stop mysqld
[root@db01 ~]# ps -ef |grep mysqld
root 7905 7664 0 03:22 pts/1 00:00:00 grep --color=auto mysqld
跳过授权表，跳过网络启动数据库
[root@db01 ~]# mysqld_safe --skip-grant-tables --skip-networking & -----跳过授权表，跳过网络
[1] 7908
[root@db01 ~]# 191101 03:26:40 mysqld_safe Logging to '/application/mysql/data/db01.err'.
191101 03:26:40 mysqld_safe Starting mysqld daemon with databases from /application/mysql/data
连接数据库
[root@db01 ~]# mysql
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 1
Server version: 5.6.44 Source distribution
Copyright (c) 2000, 2019, 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>
刷新授权表
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
创建 root 超级用户并退出
mysql> grant all on *.* to root@'localhost' identified by '123' with grant option;
Query OK, 0 rows affected (0.00 sec)
mysql> q
Bye
停止mysql服务
[root@db01 ~]# mysqladmin -uroot -p123 shutdown
Warning: Using a password on the command line interface can be insecure.
191101 03:58:41 mysqld_safe mysqld from pid file /application/mysql/data/db01.pid ended
[1]+ Done mysqld_safe --skip-grant-tables --skip-networking
[root@db01 ~]# ps -ef |grep mysqld
root 8078 7664 0 03:59 pts/1 00:00:00 grep --color=auto mysqld
启动数据库服务
[root@db01 ~]# systemctl start mysqld
[root@db01 ~]# ps -ef |grep mysqld
mysql 8085 1 8 03:59 ? 00:00:00 /application/mysql/bin/mysqld --defaults-file=/etc/my.cnf
root 8108 7664 0 03:59 pts/1 00:00:00 grep --color=auto mysqld
连接数据库
[root@db01 ~]# mysql -uroot -p123
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or g.
Your MySQL connection id is 1
Server version: 5.6.44 Source distribution
Copyright (c) 2000, 2019, 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>
查看创建的用户的权限
mysql> select * from mysql.userG
*************************** 1. row ***************************
Host: localhost
User: root
Password: *23AE809DDACAF96AF0FD78ED04B6A265E05AA257
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 -------------------------如果是N 就是不是超级用户权限
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: mysql_native_password
authentication_string:
password_expired: N
1 row in set (0.00 sec)