mysql Access denied for user ''@'localhost' to database 'mysql'

1.停止mysql服务 ：

  service mysql stop;

2.屏蔽权限;

  mysqld_safe --user=root --skip-grant-tables --skip-networking

3.登陆mysql

  mysql -u root -p

4.切换至mysql数据库

  use mysql;

5.delete from user where user='';

6.FLUSH PRIVILEGES;