最近在使用MySQL，版本为‘5.6.20’。
在官网http://dev.mysql.com/downloads/mysql/下载最新windows安装版本，之后安装。我选的是custom安装模式，设置安装路径后，一直next即可。
安装完成后，使用命令行cmd进入安装路径bin目录下，我的目录为“D:\Program Files\mysql\MySQL Server 5.6\bin”。
用root帐号连上mysql，语句为“mysql -u root”即可，然后创建一个数据库，提示如下错误：
ERROR 1044 (42000): Access denied for user ''@'localhost' to database 'mydb'。
原因是因为mysql数据库的user表里，存在用户名为空的账户即匿名账户，导致登录的时候是虽然用的是root，但实际是匿名登录的，通过错误提示里的''@'localhost'可以看出来。
由于网上大多是Linux下解决方案，但是在windows下输入命令却有不同，经过在网上查找试验，终于找到一个比较有效的方法，现整理如下：
1、cmd模式进入mysql的bin目录，输入D:\Program Files\MySQL\MySQL Server 5.6\bin>mysqld --defaults-file="D:\Program Files\MySQL\MySQL Server 5.6\my-default.ini" --console --skip-grant-tables，回车
2014-08-29 10:40:48 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use
2014-08-29 10:40:48 8108 [Note] Plugin 'FEDERATED' is disabled.
2014-08-29 10:40:48 8108 [Note] InnoDB: Using atomics to ref count buffer pool pages
2014-08-29 10:40:48 8108 [Note] InnoDB: The InnoDB memory heap is disabled
2014-08-29 10:40:48 8108 [Note] InnoDB: Mutexes and rw_locks use Windows interlocked functions
2014-08-29 10:40:48 8108 [Note] InnoDB: Memory barrier is not used
2014-08-29 10:40:48 8108 [Note] InnoDB: Compressed tables use zlib 1.2.3
2014-08-29 10:40:48 8108 [Note] InnoDB: Not using CPU crc32 instructions
2014-08-29 10:40:48 8108 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2014-08-29 10:40:48 8108 [Note] InnoDB: Completed initialization of buffer pool
2014-08-29 10:40:48 8108 [Note] InnoDB: Highest supported file format is Barracuda.
2014-08-29 10:40:57 8108 [Note] InnoDB: 128 rollback segment(s) are active.
2014-08-29 10:40:57 8108 [Note] InnoDB: Waiting for purge to start
2014-08-29 10:40:57 8108 [Note] InnoDB: 5.6.20 started; log sequence number 1625997
2014-08-29 10:40:57 8108 [Note] Server hostname (bind-address): '*'; port: 3306
2014-08-29 10:40:57 8108 [Note] IPv6 is available.
2014-08-29 10:40:57 8108 [Note] - '::' resolves to '::';
2014-08-29 10:40:57 8108 [Note] Server socket created on IP: '::'.
2014-08-29 10:40:58 8108 [Note] mysqld: ready for connections.
Version: '5.6.20' socket: '' port: 3306 MySQL Community Server (GPL)
看到这个结果就说明MySQL已经起来了。
2、再开一个dos窗口，同样切到mysql bin目录下，D:\Program Files\MySQL\MySQL Server 5.6\bin>mysql -u root mysql，回车
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.6.20 MySQL Community Server (GPL)
mysql>
已连接上mysql数据库，可以输入mysql命令了。
3、设置密码
mysql> update user set password=PASSWORD('password') where user='root';
Query OK, 2 rows affected (0.02 sec)
Rows matched: 3 Changed: 2 Warnings: 0
mysql> FLUSH PRIVILEGES;
mysql> quit
之后按正常方法连接mysql就可以了。如果不能连接，查看下mysql服务是否启动。
mysql 1449 ： The user specified as a definer ('root'@'%') does not exist 解决方法
权限问题，授权 给 root 所有sql 权限
mysql> grant all privileges on *.* to root@"%" identified by ".";
Query OK, 0 rows affected (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)