1、打开终端，输入命令：cd /usr/local/mysql/bin

2、mysql -uroot -p，用这条命令登陆时报错信息：

报错：Enter password:

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

3、打开终端输入：sudo mysqld_safe --skip-grant-tables

输出

Password:

Logging to '/usr/local/mysql/data/localhost.err'.

2018-10-10T03:21:40.6NZ mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/data

4、打开一个新的终端，输入：mysql -u root ，会看到以下输出。

Welcome to the MySQL monitor. Commands end with ; or \g.

Your MySQL connection id is 16

Server version: 5.7.23 MySQL Community Server (GPL)

Copyright (c) 2000, 2018, 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> 

5、终端输入 use mysql显示如下

Reading table information for completion of table and column names

You can turn off this feature to get a quicker startup with -A

Database changed

6、修改密码：UPDATE mysql.user SET authentication_string=PASSWORD('你的密码') WHERE User='root';

Query OK, 1 row affected, 1 warning (0.01 sec)

Rows matched: 1 Changed: 1 Warnings: 1