mysql学习之-密码管理（默认密码，修改密码，解决忘记密码）

1. mysql安装后默认没有密码，初始化安装后默认密码登录，需要马上修改root密码。

[root@mysql ~]# cat /root/.mysql_secret    --查看root账号密码

# the random password set for the root user at tue dec 13 18:59:06 2016 (local time): 7mhtyx3azel9ouf8

[root@mysql ~]# mysql -uroot -p    -- 登录mysql

enter password:               --（此处复制粘贴 7mhtyx3azel9ouf8）

welcome to the mysql monitor.  commands end with ; or \g.

your mysql connection id is 2

server version: 5.6.25

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affiliates. other names may be trademarks of their respective

owners.

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

说明：  出现mysql>   表示一切顺利成功。

2.  修改密码

mysql> set password = password('123456');   --设置密码为123456

[root@mysql etc]# mysql -uroot -p123456     --修改密码后，登录

warning: using a password on the command line interface can be insecure.

your mysql connection id is 39

server version: 5.6.25 mysql community server (gpl)

mysql>     --登录成功

3. 忘记mysql数据库root的密码后，如何修改密码。

[root@mysql etc]# service mysql stop   --停止mysql进程

shutting down mysql.... success! 

[root@mysql etc]# mysqld_safe --skip-grant-tables&  --启动mysql时不启动grant-tables，授权表。执行后出现下面画面，另起一个新会话。

[1] 3574

[root@mysql etc]# 161215 06:13:53 mysqld_safe logging to '/var/lib/mysql/mysql.err'.

161215 06:13:53 mysqld_safe starting mysqld daemon with databases from /var/lib/mysql

[root@mysql ~]# ps -ef|grep mysql   --查看mysql进程是否起来

root       3467   3440  0 05:29 pts/2    00:00:00 mysql -uandy -px xx

root       3574   2845  0 06:13 pts/0    00:00:00 /bin/sh /usr/bin/mysqld_safe --skip-grant-tables

mysql      3677   3574  2 06:13 pts/0    00:00:00 /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-

mysql> update user set password=password('cccccc') where user='root';   --更改root密码

query ok, 4 rows affected (0.04 sec)

rows matched: 4  changed: 4  warnings: 0

mysql> flush privileges;    --权限更新

query ok, 0 rows affected (0.00 sec)

[root@mysql ~]# mysql -uroot -p123456    --使用旧密码登录，发现不行，说明密码已经更新

error 1045 (28000): access denied for user 'root'@'localhost' (using password: yes)

[root@mysql ~]# mysql -uroot -pcccccc   --新密码登录成功

mysql>