MySQL 权限管理的注意事项

㈠ 认证和授权 认证：who am I ？ 授权：what I can do ？ 认证实际上就是一个验证凭证的过程、而进入MySQL 需要出示的凭证有：

 ㈠ 认证和授权

认证：who am I ？

授权：what I can do ？

认证实际上就是一个验证凭证的过程、而进入MySQL 需要出示的凭证有：host、username、password

连接MySQL 常见有 2 种：

① TCP/IP 连接

加 -h 参数、通过TCP/IP 连接MySQL 实例、mysql.user 对来者进行认证

② Socket

-S 参数 、只能在 MySQL 客户端和实例在同一台服务器上使用

㈡ 缺省有 2 个高危险用户：

㈢ % 不是万能的、至少无法替代 localhost、而 MySQL 默认却是以 localhost登陆

mysql> grant all on *.* to 'david'@'%' identified by 'Oracle';
Query OK, 0 rows affected (0.05 sec)

[mysql@odd ~]$ mysql -udavid -poracle
ERROR 1045 (28000): Access denied for user 'david'@'localhost' (using password: YES)
[mysql@odd ~]$ mysql -udavid -poracle -h 127.0.0.1
ERROR 1045 (28000): Access denied for user 'david'@'localhost' (using password: YES)

mysql> grant all on *.* to 'david'@'localhost' identified by 'oracle';
Query OK, 0 rows affected (0.01 sec)

[mysql@odd ~]$ mysql -udavid -poracle
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 9
Server version: 5.5.16-log Source distribution

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