mysql 安裝完成後登陸不了mysql的 shell 即mysql>遇到：ERROR 1045 (28000): Access denied for user 'root'@'localhost‘，

mysql 安裝完成後登陸不了mysql的 shell 即mysql>遇到：ERROR 1045 (28000): Access denied for user 'root'@'localhost‘，

[root@hzswtb2-mpc ~]# mysql
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)

遇到：ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)

網上找了很多的文章還是沒有解決我的問題；

1.首先可以確認的是mysql 命令列 sql命令關鍵字是不區分大小寫；在mysql 5.1.51版本；

2.先將正常啟動的mysqld stop掉；

3.再以繞過root口令檢查的方式 啟動 mysqld；

 

以下是解決經過：

1.先將正常啟動的mysqld stop掉

[root@hzswtb2-mpc ~]# service mysqld stop
Stopping mysqld:                                           [  OK  ]

2.用繞過root口令檢查的方式 啟動 mysql 伺服器，並且讓其在後台運行；

[root@hzswtb2-mpc ~]# mysqld_safe --user=mysql --skip-grant-tables --skip-networking &
[1] 25513
[root@hzswtb2-mpc ~]# 141215 15:00:16 mysqld_safe Logging to '/var/log/mysqld.log'.
141215 15:00:16 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql

3. mysql斷行符號，進入mysql shell，按照前人留下的方法， update user表中的 root 使用者的密碼，結果發現 0 rows affected，再select 細看 user 表是空的；

[root@hzswtb2-mpc ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.1.51 Source distribution

mysql> UPDATE user SET PASSWORD=PASSWORD('123456') where USER='root';       
Query OK, 0 rows affected (0.00 sec)
Rows matched: 0  Changed: 0  Warnings: 0

mysql>  use mysql
Database changed
mysql> show tables;
+---------------------------+
| Tables_in_mysql           |
+---------------------------+
| columns_priv              |
| db                        |
| event                     |
| func                      |
| general_log               |
| help_category             |
| help_keyword              |
| help_relation             |
| help_topic                |
| host                      |
| ndb_binlog_index          |
| plugin                    |
| proc                      |
| procs_priv                |
| servers                   |
| slow_log                  |
| tables_priv               |
| time_zone                 |
| time_zone_leap_second     |
| time_zone_name            |
| time_zone_transition      |
| time_zone_transition_type |
| user                      |
+---------------------------+
23 rows in set (0.00 sec)

mysql> select * from user;
Empty set (0.00 sec)

4.在user表 insert 一個名稱為root的使用者； 

mysql> insert into user(Host,User,Password,Select_priv,Insert_priv) VALUES('localhost','root',PASSWORD('pass3'),'Y','Y');
Query OK, 1 row affected, 3 warnings (0.00 sec)

5.看到有個root使用者了；

mysql> select * from user                
    -> ;
+-----------+------+-------------------------------------------+-------------+-------------+-------------+-------------+-------------+-----------+-------------+---------------+--------------+-----------+------------+-----------------+------------+------------+--------------+------------+-----------------------+------------------+--------------+-----------------+------------------+------------------+----------------+---------------------+--------------------+------------------+------------+--------------+----------+------------+-------------+--------------+---------------+-------------+-----------------+----------------------+
| Host      | User | Password                                  | 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 | ssl_type | ssl_cipher | x509_issuer | x509_subject | max_questions | max_updates | max_connections | max_user_connections |
+-----------+------+-------------------------------------------+-------------+-------------+-------------+-------------+-------------+-----------+-------------+---------------+--------------+-----------+------------+-----------------+------------+------------+--------------+------------+-----------------------+------------------+--------------+-----------------+------------------+------------------+----------------+---------------------+--------------------+------------------+------------+--------------+----------+------------+-------------+--------------+---------------+-------------+-----------------+----------------------+
| localhost | root | *35B5E90BC4F5AE5D02ED515DF6B61141F24EDA02 | Y           | Y           | N           | N           | N           | N         | N           | N             | N            | N         | N          | N               | N          | N          | N            | N          | N                     | N                | N            | N               | N                | N                | N              | N                   | N                  | N                | N          | N            |          |            |             |              |             0 |           0 |               0 |                    0 |
+-----------+------+-------------------------------------------+-------------+-------------+-------------+-------------+-------------+-----------+-------------+---------------+--------------+-----------+------------+-----------------+------------+------------+--------------+------------+-----------------------+------------------+--------------+-----------------+------------------+------------------+----------------+---------------------+--------------------+------------------+------------+--------------+----------+------------+-------------+--------------+---------------+-------------+-----------------+----------------------+
1 row in set (0.00 sec)

6 再更新 root 使用者的密碼，也能返回成功了；

mysql> UPDATE user SET Password = PASSWORD('newpass') WHERE user = 'root';
Query OK, 1 row affected (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)

mysql> exit

7.stop 剛才的 mysql服務，以正常方式重新啟動mysql 伺服器，mysql -u root -p  密碼是newpass

[root@hzswtb2-mpc ~]# service mysqld stop
141215 16:12:24 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended
Stopping mysqld:                                           [  OK  ]
[1]+  Done                    mysqld_safe --user=mysql --skip-grant-tables --skip-networking
[root@hzswtb2-mpc ~]# service mysqld start
Starting mysqld:                                           [  OK  ]
[root@hzswtb2-mpc ~]#
[root@hzswtb2-mpc ~]# mysql
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
[root@hzswtb2-mpc ~]# mysql -u root -p
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.1.51 Source distribution

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