按照我之前安装5.6的安装方法（MySQL免安装版下载与配置）安装5.7的时候出现问题：
mysql服务无法启动，服务没有报任何错误
其实在这学期开始学习mysql的时候，就听老师同学说，登录不了的问题，当时没有在意，也是因为电脑上早就安装了mysql5.6，也就没有在意这个问题。这两天win10系统出问题，重装了win7，安装5.7的时候出现了这个问题。
之前的版本默认密码为空，具体版本不太清楚，反正5.6密码是空。5.7的安全性提升，在linux安装5.7的时候，安装完成后会生成一个随机性密码，存储在root/.mysql_secret中，如果没有这个文件，去系统日志中查找password，就应该能找到。
但是windows下就不知道如何解决了，不过最后还是找到了解决方法。
解决方法：
来自：windows MySql 5.7.9，启动不了。缺少data
然而并不是缺少data文件夹，将my-default.ini文件改名为my.ini，移动到bin/目录下，在bin/下执行命令 mysqld --initialize --user=mysql --console ，这条命令估计是初始化的命令
然后启动服务 net start mysql
命令行显示贴在这
Microsoft Windows [版本 6.1.7601]
版权所有 (c) 2009 Microsoft Corporation。保留所有权利。
C:\Windows\system32>cd ..
C:\Windows>cd ..
C:\>cd mysql-5.7.13-winx64/Boot
系统找不到指定的路径。
C:\>cd mysql-5.7.13-winx64\bin
C:\mysql-5.7.13-winx64\bin>mysqld install
Service successfully installed.
C:\mysql-5.7.13-winx64\bin>net start mysql
MySQL 服务正在启动 .
MySQL 服务无法启动。
服务没有报告任何错误。
请键入 NET HELPMSG 3534 以获得更多的帮助。
C:\mysql-5.7.13-winx64\bin>net start mysql
MySQL 服务正在启动 .
MySQL 服务无法启动。
服务没有报告任何错误。
请键入 NET HELPMSG 3534 以获得更多的帮助。
C:\mysql-5.7.13-winx64\bin>mysqld --initialize --user=mysql --console
2016-06-21T14:07:20.922112Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is
deprecated. Please use --explicit_defaults_for_timestamp server option (see doc
umentation for more details).
2016-06-21T14:07:22.669315Z 0 [Warning] InnoDB: New log files created, LSN=45790
2016-06-21T14:07:23.106116Z 0 [Warning] InnoDB: Creating foreign key constraint
system tables.
2016-06-21T14:07:23.308916Z 0 [Warning] No existing UUID has been found, so we a
ssume that this is the first time that this server has been started. Generating
a new UUID: 79c8386d-37b9-11e6-9709-74867a6179b7.
2016-06-21T14:07:23.340116Z 0 [Warning] Gtid table is not ready to be used. Tabl
e 'mysql.gtid_executed' cannot be opened.
2016-06-21T14:07:23.355716Z 1 [Note] A temporary password is generated for root@
localhost: rr9.8h74twfR
C:\mysql-5.7.13-winx64\bin>mysql -uroot -prr9.8h74twfR
mysql: [Warning] Using a password on the command line interface can be insecure.
ERROR 2003 (HY000): Can't connect to MySQL server on 'localhost' (10061)
C:\mysql-5.7.13-winx64\bin>net start mysql
MySQL 服务正在启动 .
MySQL 服务已经启动成功。
C:\mysql-5.7.13-winx64\bin>mysql -uroot -prr9.8h74twfR
mysql: [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 2
Server version: 5.7.13
Copyright (c) 2000, 2016, 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> set password=password('');
Query OK, 0 rows affected, 1 warning (0.00 sec)
mysql> exit
Bye
C:\mysql-5.7.13-winx64\bin>mysql -uroot
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.13 MySQL Community Server (GPL)
Copyright (c) 2000, 2016, 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> exit
Bye
C:\mysql-5.7.13-winx64\bin>