下面的文章主要介绍了用户密码的设置方式以及密码的修改方式以及mysql自带的测试库test库安全建议
A root account password can be set several ways. The following discussion demonstrates three methods:
Use the SET PASSWORD statement #使用set password方式
Use the UPDATE statement #使用update方式
Use the mysqladmin command-line client program #使用mysqladmin方式
To assign passwords using SET PASSWORD, connect to the server as root and issue a SET PASSWORD statement for each root account listed in the mysql.user table.
For Windows, do this:（windows设置方式）
shell>mysql -u root
mysql>SET PASSWORD FOR 'root'@'localhost' = PASSWORD('newpwd');
mysql>SET PASSWORD FOR 'root'@'127.0.0.1' = PASSWORD('newpwd');
mysql>SET PASSWORD FOR 'root'@'::1' = PASSWORD('newpwd');
mysql>SET PASSWORD FOR 'root'@'%' = PASSWORD('newpwd');
The last statement is unnecessary if themysql.usertable has norootaccount with a host value of%.
For Unix, do this:
shell>mysql -u root #使用root帐号登录，登陆后修改相应的密码
mysql>SET PASSWORD FOR 'root'@'localhost' = PASSWORD('newpwd');
mysql>SET PASSWORD FOR 'root'@'127.0.0.1' = PASSWORD('newpwd');
mysql>SET PASSWORD FOR 'root'@'::1' = PASSWORD('newpwd');
mysql>SET PASSWORD FOR 'root'@'host_name' = PASSWORD('newpwd');
You can also use a single statement that assigns a password to all root accounts by using UPDATE to modify the mysql.user table directly. This method works on any platform:
由于mysql的用户是由用户名和授权登录的地址段组成，可以使用下面的命令一次性更新所有的root密码
shell>mysql -u root
mysql>UPDATE mysql.user SET Password = PASSWORD('newpwd') WHERE User = 'root';
#更新mysql user表中的root的密码
mysql>FLUSH PRIVILEGES; (注意update方式更新的密码，必须刷新权限，如果不刷新更新的密码不生效)
The FLUSH statement causes the server to reread the grant tables. Without it, the password change remains unnoticed by the server until you restart it.
To assign passwords to the root accounts using mysqladmin, execute the following commands:
#mysqladmin方式更新用户密码（windows和linux都有效）
shell>mysqladmin -u root password "newpwd"
shell>mysqladmin -u root -hhost_name password "newpwd"
Those commands apply both to Windows and to Unix. The double quotation marks around the password are not always necessary, but you should use them if the password contains spaces or other characters that are special to your command interpreter.
注意 mysqladmin命令不能用于下面两个用户的更新
1）'root'@'127.0.0.1'
2） 'root'@'::1'
The mysqladmin method of setting the root account passwords does not work for the'root'@'127.0.0.1' or 'root'@'::1'account. Use the SET PASSWORD method shown earlier.
After the root passwords have been set, you must supply the appropriate password whenever you connect as root to the server. For example, to shut down the server with mysqladmin, use this command:
shell>mysqladmin -u root -p shutdown Enter password:(enter root password here)
The mysql commands in the following instructions include a-poption based on the assumption that you have assigned the root account passwords using the preceding instructions and must specify that password when connecting to the server.
匿名用户设置密码方式
Assigning Anonymous Account Passwords
To assign passwords to the anonymous accounts, connect to the server as root, then use either SET PASSWORD or UPDATE.
方式一：
To use SET PASSWORD on Windows, do this:
shell>mysql -u root -p
Enter password:(enter root password here)
mysql>SET PASSWORD FOR ''@'localhost' = PASSWORD('newpwd');
To use SET PASSWORD on Unix, do this:
shell>mysql -u root -p
Enter password:(enter root password here)
mysql>SET PASSWORD FOR ''@'localhost' = PASSWORD('newpwd');
mysql>SET PASSWORD FOR ''@'host_name' = PASSWORD('newpwd');
方式二：
To set the anonymous-user account passwords with a single UPDATE statement, do this (on any platform):
shell>mysql -u root -p
Enter password:(enter root password here)
mysql>UPDATE mysql.user SET Password = PASSWORD('newpwd')->WHERE User = '';
mysql>FLUSH PRIVILEGES;
The FLUSH statement causes the server to reread the grant tables. Without it, the password change remains unnoticed by the server until you restart it.
Removing Anonymous Accounts
移除匿名帐号的方法
If you prefer to remove any anonymous accounts rather than assigning them passwords, do so as follows on Windows:
shell>mysql -u root -p
Enter password:(enter root password here)
mysql>DROP USER ''@'localhost';
On Unix, remove the anonymous accounts like this:
shell>mysql -u root -p
Enter password:(enter root password here)
mysql>DROP USER ''@'localhost';
mysql>DROP USER ''@'host_name';
test数据库的安全风险
Securing Test Databases
By default, the mysql.db table contains rows that permit access by any user to the test database and other databases with names that start with test_. (These rows have an empty User column value, which for access-checking purposes matches any user name.) This means that such databases can be used even by accounts that otherwise possess no privileges. If you want to remove any-user access to test databases, do so as follows:
test数据库任何账户都可以访问，这样就存在着风险，用户恶意写入数据使数据库写满
shell>mysql -u root -p
Enter password:(enter root password here)
mysql>DELETE FROM mysql.db WHERE Db LIKE 'test%';
mysql>FLUSH PRIVILEGES;
The FLUSH statement causes the server to reread the grant tables. Without it, the privilege change remains unnoticed by the server until you restart it.
With the preceding change, only users who have global database privileges or privileges granted explicitly for thetestdatabase can use it. However, if you prefer that the database not exist at all, drop it:
mysql>DROP DATABASE test;