Mysql教程:教你为root用户指定一个目录
在你自己安装了一个新的MySQL服务器后,你需要为MySQL的root用户指定一个目录(缺省无口令),否则如果你忘记这点,你将你的MySQL处于极不安全的状态(至少在一段时间内)。 在Unix(Linux)上,在按照手册的指令安装好MySQL后,你必须运行mysql_install_db脚本建
在你自己安装了一个新的MySQL服务器后,你需要为MySQL的root用户指定一个目录(缺省无口令),否则如果你忘记这点,你将你的MySQL处于极不安全的状态(至少在一段时间内)。
在Unix(Linux)上,在按照手册的指令安装好MySQL后,你必须运行mysql_install_db脚本建立包含授权表的mysql数据库和初始权限。在Windows上,运行分发中的Setup程序初始化数据目录和mysql数据库。假定服务器也在运行。
当你第一次在机器上安装MySQL时,mysql数据库中的授权表是这样初始化的:
你可以从本地主机(localhost)上以root连接而不指定口令。root用户拥有所有权限(包括管理权限)并可做任何事情。(顺便说明,MySQL超级用户与Unix超级用户有相同的名字,他们彼此毫无关系。)
匿名访问被授予用户可从本地连接名为test和任何名字以test_开始的数据库。匿名用户可对数据库做任何事情,但无管理权限。
从本地主机多服务器的连接是允许的,不管连接的用户使用一个localhost主机名或真实主机名。如:
% mysql -h localhost test
% mysql -h pit.snake.net test
你以root连接MySQL甚至不指定口令的事实只是意味着初始安装不安全,所以作为管理员的你首先要做的应该是设置root口令,然后根据你设置口令使用的方法,你也可以告诉服务器重载授权表是它知道这个改变。(在服务器启动时,它重载表到内存中而可能不知道你已经修改了它们。)
对MySQL 3.22和以上版本,你可以用mysqladmin设置口令:
% mysqladmin -u root password yourpassword
对于MySQL的任何版本,你可以用mysql程序并直接修改mysql数据库中的user授权表:
% mysql -u root mysql
mysql>UPDATE user SET password=PASSWORD("yourpassword") WHERE User="root";
如果你有MySQL的老版本,,使用mysql和UPDATE。
在你设置完口令后,通过运行下列命令检查你是否需要告诉服务器重载授权表:
% mysqladmin -u root status
如果服务器仍然让你以root而不指定口令而连接服务器,重载授权表:
% mysqladmin -u root reload
在你设置了root的口令后(并且如果需要重载了授权表),你将需要在任何时候以root连接服务器时指定口令。
注:更多精彩文章请关注三联编程教程栏目。

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