误删除 mySQL 用户解决办法

误删除用户解决办法

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删除用户

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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

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恢复用户

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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
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[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.user\G
*************************** 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)

注意：以上只能在存在数据的时候使用，如果没有数据直接初始化就可以。