ERROR 1045 (28000): Access denied for user 'root'@'localhost'

        我是在linux下安装了mysql，服务都启动完成之后在本机去连mysql数据库，进入到mysql安装目录下的bin目录，输入：./mysql -u root -p ，发现一直提示：ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)。

        原来是mysql默认给数据库的root用户加了密码，该密码不是操作系统的密码，此时需要停掉mysql服务，然后进入安全模式去设置，操作如下：

[root@localhost ~]# /etc/rc.d/init.d/mysql

[root@localhost ~]# ./mysqld_safe --user=mysql --skip-grant-tables --skip-networking &

[root@localhost ~]# ./mysql -u root mysql

mysql> select Host, User, Password,password_expired from user where user='root' and host='root' or host='localhost';
ERROR 1054 (42S22): Unknown column 'Password' in 'field list'

mysql> select * from user where user='root' and host='root' or host='localhost';

 

发现字段不是叫做password，而是authentication_string

mysql> select Host, User, authentication_string,password_expired from user where user='root' and host='root' or host='localhost';
+-----------+-----------+-------------------------------------------+------------------+
| Host      | User      | authentication_string                     | password_expired |
+-----------+-----------+-------------------------------------------+------------------+
| localhost | mysql.sys | *THISISNOTAVALIDPASSWORDTHATCANBEUSEDHERE | N                |
| localhost | root      | *9BB84292F4643547E34917D364B0C094C76E7306 | Y                |
+-----------+-----------+-------------------------------------------+------------------+
2 rows in set (0.00 sec)

mysql> UPDATE user SET authentication_string=PASSWORD('myegoo3466') where USER='root';
Query OK, 1 row affected, 1 warning (0.01 sec)
Rows matched: 1  Changed: 1  Warnings: 1

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

mysql> quit;
Bye

[root@localhost bin]# /etc/rc.d/init.d/mysql restart

重启mysql服务之后重新连就ok了

[root@localhost bin]# ./mysql -u root -p
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.12

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mysql>

接下来可以在mysql里面操作任何你想操作的东西啦！