创建Mysql用户及赋予用户权限
1通过help查看grant命令帮助
1.通过在mysql中输入“help grant”得到如下帮助信息。
mysql> help grant;
……省略部分…….
CREATE USER 'jeffrey'@'localhost' IDENTIFIED BY 'mypass';
GRANT ALL ON db1.* TO 'jeffrey'@'localhost';
GRANT SELECT ON db2.invoice TO 'jeffrey'@'localhost';
GRANT USAGE ON *.* TO 'jeffrey'@'localhost' WITH MAX_QUERIES_PER_HOUR 90;
……省略部分…….2.运维人员比较常用的创建用户的方法是，使用grant命令在创建用户的同时进行权限授权具体授权例子为：
GRANT ALL ON db1.* TO 'jeffrey'@'localhost' IDENTIFIED BY 'mypass';3.上述grant命令帮助里还提供了一个先用create命令创建用户，然后再用Grant授权的方法，即创建用户和授权权限分开进行，列如：
CREATE USER 'jeffrey'@'localhost' IDENTIFIED BY 'mypass';
GRANT ALL ON db1.* TO 'jeffrey'@'localhost';以上两条命令相当于下面一条命令
GRANT ALL ON db1.* TO 'jeffrey'@'localhost' IDENTIFIED BY 'mypass';2 通过grant命令创建用户并授权
1.Grant命令简单语法如下
Grant all privileges on dbname.* to username@localhost identified by ‘passwd’2.列表说明
3.案例：创建用户zhangsan,对test库具备所有权限，允许从localhost主机登录管理数据库，密码是zhangsan123。
实现上述操作的具体命令为
mysql> grant all privileges on test.* to 'zhangsan'@'localhost' identified by 'zhangsan123';
Query OK, 0 rows affected (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)检查授权用户zhangsan的具体权限
mysql> show grants for 'zhangsan'@'localhost';
Grants for zhangsan@localhost
GRANT USAGE ON *.* TO 'zhangsan'@'localhost' IDENTIFIED BY PASSWORD '*7E72D61D7B957897AA8ECED9A9397B649BE3B546' |
GRANT ALL PRIVILEGES ON `test`.* TO 'zhangsan'@'localhost'
2 rows in set (0.00 sec)3 Create和grant配合法
1.首先创建用户username及密码passwd,授权主机localhost。
CREATE USER 'username'@'localhost' IDENTIFIED BY 'passwd';
mysql> create user 'lisi'@'localhost' identified by 'kisi123';
Query OK, 0 rows affected (0.01 sec)
mysql> show grants for 'lisi'@'localhost';
Grants for lisi@localhost GRANT USAGE ON *.* TO 'lisi'@'localhost' IDENTIFIED BY PASSWORD '*686008E0BFD16925072B84AA099EB5BC8375C35B'
1 row in set (0.00 sec)默认权限是USAGE，及连接的权限，因为此时还没有权限。
2.然后授权localhost主机上通过用户username管理test数据库的所有权限，无需密码。
mysql> grant all on test.* to 'lisi'@'localhost';
Query OK, 0 rows affected (0.00 sec)
mysql> show grants for 'lisi'@'localhost';
Grants for lisi@localhost
GRANT USAGE ON *.* TO 'lisi'@'localhost' IDENTIFIED BY PASSWORD '*686008E0BFD16925072B84AA099EB5BC8375C35B'
GRANT ALL PRIVILEGES ON `test`.* TO 'lisi'@'localhost' 提示：可以看到默认权限是usage即连接的权限，后面又增加了ALL权限。
4 授权局域网内主机远程连接数据库
根据grant命令的语法我们知道，test@localhost位置为授权访问数据库的主机，localhost可以用域名，IP地址或者IP段来替代，因此要授权局域网内主机可以通过如下方法来实现。
a.百分号匹配法
system@ceshi 01:5945->grant all privileges on test.* to 'zbf'@'192.168.1.%' identified by 'zbf123';
Query OK, 0 rows affected (0.01 sec)
system@ceshi 01:5950->show grants for 'zbf'@'192.168.1.%';
Grants for zbf@192.168.1.%
GRANT USAGE ON *.* TO 'zbf'@'192.168.1.%' IDENTIFIED BY PASSWORD '*E2190B1F46FD9E171DD25B61138EA7F4F4D82B8C'
GRANT ALL PRIVILEGES ON `test`.* TO 'zbf'@'192.168.1.%'
2 rows in set (0.00 sec)
system@ceshi 02:0023->flush privileges;
Query OK, 0 rows affected (0.00 sec)b.子网掩码配置法
system@ceshi 02:3013->grant all privileges on test.* to 'wwn'@'192.168.1.0/255.255.255.0' identified by 'wwn520';
Query OK, 0 rows affected (0.01 sec)
system@ceshi 02:3127->flush privileges;
Query OK, 0 rows affected (0.00 sec)通过mysql客户端连接异地数据库服务：
1.本地mysql –uroot –pzbf666连接数据库相当于mysql –uroot –pzbf666 –h localhost
2.要远程连接192.168.1.108的数据库，命令为 mysql -uwwn -pwwn520 -h 192.168.1.108
3.通过php服务器连接mysql服务器的代码写法为
<?php
//$link_id=mysql_connect('主机名','用户','密码')；
$link_id=mysql_connect（'192.168.1.108','wwn','wwn123'）;
if($link_id){
echo "mysql successful by wwn";
}else{
echo mysql_error();
}
?>9.8.5 MySQL用户可以授权的权限有哪些？
通过实验获得ALL PRIVILEGES包括哪些权限
1.先看看有哪些用户
system@ceshi 03:3751->select user,host from mysql.user;
+--------+---------------------------+
| user | host |
+--------+---------------------------+
| zbf| 192.168.1.% |
| wwn| 192.168.1.0/255.255.255.0 |
| system | localhost |
+--------+---------------------------+2.看看授权过的wwn的权限
system@ceshi 03:3920->show grants for 'wwn'@'192.168.1.0/255.255.255.0';
| Grants for wwn@192.168.1.0/255.255.255.0
GRANT USAGE ON *.* TO 'wwn'@'192.168.1.0/255.255.255.0' IDENTIFIED BY PASSWORD '*C9CE90EB588AA17159BB7C612DC7B34259AC0816' |
| GRANT ALL PRIVILEGES ON `test`.* TO 'wwn'@'192.168.1.0/255.255.255.0' 注意这个地方的test.，我们后面取消只读权限的时候也这样写成test.
这时候查看还是ALL PRIVILEGES权限，没有细分。
3.取消wwn的只读权限（SELECT）。
(1) 先看一下帮助，帮助里面提供了语法，revoke在sql语言介绍那节已经提到过了，意思是取消授权。
system@ceshi 03:4001->help revoke
……省略……….
The REVOKE statement enables system administrators to revoke privileges
from MySQL accounts. Each account name uses the format described in
http://dev.mysql.com/doc/refman/5.1/en/account-names.html.For example:
REVOKE INSERT ON *.* FROM 'jeffrey'@'localhost';
If you specify only the user name part of the account name, a host name
part of '%' is used.
……省略……(2) 取消授权，将ALL PRIVILEGES权限细分。
system@ceshi 03:4909->REVOKE INSERT ON test.* FROM 'wwn'@'192.168.1.0/255.255.255.0';
Query OK, 0 rows affected (0.00 sec)
system@ceshi 03:5216->flush privileges;
Query OK, 0 rows affected (0.00 sec)(3)再查看一下用户wwn的权限就已经被细分了。
system@ceshi 03:5224->show grants for 'wwn'@'192.168.1.0/255.255.255.0';
GRANT USAGE ON *.* TO 'wwn'@'192.168.1.0/255.255.255.0' IDENTIFIED BY PASSWORD '*C9CE90EB588AA17159BB7C612DC7B34259AC0816'
GRANT SELECT, UPDATE, DELETE, CREATE, DROP, REFERENCES, INDEX, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE, CREATE VIEW, SHOW VIEW, CREATE ROUTINE, ALTER ROUTINE, EVENT, TRIGGER ON `test`.* TO 'wwn'@'192.168.1.0/255.255.255.0提示：此时wwn用户的权限，ALL PRIVILEGES权限已经被细分了。按照下面的步骤我们可以更加清楚的知道ALL PRIVILEGES的权限包括哪些内容。
(1) 我们用-e 不登录mysql数据库直接查看用户wwn有哪些权限
[root@localhost ~]# mysql -usystem -pzbf666 -e "show grants for 'wwn'@'192.168.1.0/255.255.255.0';"|grep -i grant|tail -1
GRANT SELECT, UPDATE, DELETE, CREATE, DROP, REFERENCES, INDEX, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE, CREATE VIEW, SHOW VIEW, CREATE ROUTINE, ALTER ROUTINE, EVENT, TRIGGER ON `test`.* TO 'wwn'@'192.168.1.0/255.255.255.0'(2) 查看用户wwn有哪些权限之后，我们要把有用的筛选出来。grep的-i参数是忽略大小写的意思。
[root@localhost ~]# mysql -usystem -pzbf666 -e "show grants for 'wwn'@'192.168.1.0/255.255.255.0';"|grep -i grant|tail -1|tr ',' '
'>all1.txt(3) 好我们查看一下过滤的内容，下面内容就是用户wwn所具有的所有权限。
[root@localhost ~]# cat all1.txt -n
1 SELECT
2 UPDATE
3 INSERT
4 DELETE
5 CREATE
6 DROP
7 REFERENCES
8 INDEX
9 ALTER
10 CREATE TEMPORARY TABLES
11 LOCK TABLES
12 EXECUTE
13 CREATE VIEW
14 SHOW VIEW
15 CREATE ROUTINE
16 ALTER ROUTINE
17 EVENT
18 TRIGGER ON注意：在授权时可以授权用户最小的满足业务的权限，而不是一味的授权“ALL PRIVILEGES”
9.8.6 企业环境授权用户权限
1.博客，CMS等产品的数据库授权
对于web连接用户授权尽量采用最小化规则，很多开源软件都是web界面安装，因此，在安装期间除了select,insert,update,delete4个权限外，还需要create,drop等比较危险的权限。
system@ceshi 04:5606->grant select,insert,update,delete,create,drop on blog.* to 'blog'@'192.168.1.%' identified by '1b23456';
Query OK, 0 rows affected (0.00 sec)
system@ceshi 04:5907->flush privileges;
Query OK, 0 rows affected (0.00 sec)常规情况下授权select,insert,update,delete4个权限即可，有的开源软件，列如discuzbbs，还需要create,drop等比较危险的权限。
2.生成数据库表之后，要收回create、drop授权
system@ceshi 04:5925->help revoke
REVOKE ALL PRIVILEGES, GRANT OPTION
FROM user [, user] ...
REVOKE INSERT ON *.* FROM 'jeffrey'@'localhost';
2 rows in set (0.01 sec)
system@ceshi 05:1327->REVOKE CREATE,DROP ON blog.* FROM 'blog'@'192.168.1.%';
Query OK, 0 rows affected (0.00 sec)
system@ceshi 05:1452->flush privileges;
Query OK, 0 rows affected (0.00 sec)
system@ceshi 05:1543->show grants for 'blog'@'192.168.1.%'G;
*************************** 1. row ***************************
Grants for blog@192.168.1.%: GRANT USAGE ON *.* TO 'blog'@'192.168.1.%' IDENTIFIED BY PASSWORD '*6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9'
*************************** 2. row ***************************
Grants for blog@192.168.1.%: GRANT SELECT, INSERT, UPDATE, DELETE ON `blog`.* TO 'blog'@'192.168.1.%'
2 rows in set (0.00 sec)