mysql命令行下用户管理方法分享_MySQL
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mysql安装后好,会有一个名字为mysql的数据库,存放用户的表是user,mysql数据库的用户管理就是围绕这个表展开的,当然还有一些表,例如:tables_priv,procs_priv,clumns_priv,information_schema数据库里面的USER_PRIVILEGES等。
如果有mysql管理工具phpmyadmin的话,我们可以通过图形画界面来对用户进行管理,但是如果没有phpmyadmin这样的管理工具怎么办呢?这个时候,我们可以通过命令行执行sql语句来管理mysql的用户。
一,添加用户
1,create user
语法:
CREATE USER user_specification
[, user_specification] ...
user_specification:
user [IDENTIFIED BY [PASSWORD] 'password']
实例:
mysql> create user '44'@'127.0.0.1'; //创建一个44用户
Query OK, 0 rows affected (0.00 sec)
mysql> create user '33'@'localhost' identified by 'aaaa'; //创建一个33用户,密码为aaaa
Query OK, 0 rows affected (0.00 sec)
mysql> select * from mysql.user where user='33' or user='44'/G; //查看一下mysql下的user
create user 虽然可以创建用户,但是它只是创建用户,并没有给用户分配置权限,所以一般被 grant命令所取代。
2,grant
语法:
GRANT
priv_type [(column_list)]
[, priv_type [(column_list)]] ...
ON [object_type] priv_level
TO user_specification [, user_specification] ...
[REQUIRE {NONE | ssl_option [[AND] ssl_option] ...}]
[WITH with_option ...]
object_type:
TABLE
| FUNCTION
| PROCEDURE
priv_level:
*
| *.*
| db_name.*
| db_name.tbl_name
| tbl_name
| db_name.routine_name
user_specification:
user [IDENTIFIED BY [PASSWORD] 'password']
ssl_option:
SSL
| X509 #要求x509证书
| CIPHER 'cipher' #加密算法
| ISSUER 'issuer' #证书发行商
| SUBJECT 'subject' #主题
with_option:
GRANT OPTION
| MAX_QUERIES_PER_HOUR count #每小时最多执行多少条sql
| MAX_UPDATES_PER_HOUR count #每小时最多更新多少条数据
| MAX_CONNECTIONS_PER_HOUR count #每小时最大的联接数是多少
| MAX_USER_CONNECTIONS count #最大用户联接数
不要被上面的语法吓倒,其实理解什么意思,就很容易掌握。我是这样理解的。
grant 权限 on 应用范围(数据库表,方法等) to 用户(用@隔开,前面是用户名后面是主机名'用户名'@'主机名') identified by 密码 require 要求什么的 with 对用户的进行的执行sql的条数控制。
个人觉得,只要记得上面几个红色的关键词,基本上这个命令就掌握了。
Privilege | Meaning |
---|---|
ALL [PRIVILEGES] |
所有权限 |
ALTER |
可以使用alter table |
ALTER ROUTINE |
可以使用alter routine
|
CREATE |
可以创建数据库和表 |
CREATE ROUTINE |
可以使用create routine |
CREATE TEMPORARY TABLES |
可以使用临时表 |
CREATE USER |
可以对用户进添加,删除,重命名,撤销权限 |
CREATE VIEW |
可以创建和修改视图 |
DELETE |
可以删除数据 |
DROP |
可能删除数据库,表,视图等 |
EVENT |
可以使用事件高度器 |
EXECUTE |
可以执行routine |
FILE |
可以在服务器读写文件 |
GRANT OPTION |
用户有权对自己添加的用衣授权 |
INDEX |
可以创建,删除索引 |
INSERT |
可以插入 |
LOCK TABLES |
可以锁定表 |
PROCESS |
可以使用SHOW PROCESSLIST来查看mysql当前用户的执行sql情况
|
REFERENCES |
Not implemented |
RELOAD |
可以使用刷新功能 |
REPLICATION CLIENT |
用户可以进行主从同步 |
REPLICATION SLAVE |
主从同步时,从服务器可以从主服务器读取binary log |
SELECT |
可以查找 |
SHOW DATABASES |
可以使用show databases来查看所有数据库 |
SHOW VIEW |
可以使用show view来查看视图 |
SHUTDOWN |
可以使用mysqladmin中的参数shutdown |
SUPER |
Enable use of other adminstrative operations such as CHANGE MASTER TO , KILL , PURGE BINARY LOGS , SET GLOBAL , and mysqladmin debug command |
TRIGGER |
可以使用触发器 |
UPDATE |
可以进行理会新操作 |
USAGE |
无特权 |
实例:
grant all ON test.* TO 'test'@'localhost'; //test用户拥有test数据库下的所有操作
grant select,update on test.user to 'test'@'localhost'; //test用户可以对test数据库下user表,进行查找和更新操作
//test用户的的密码是111111,对user表中的name字段有读取权限,对id,name有更新权限
grant select(name),update(id,name) on test.user to 'test'@'localhost' identified by '111111';
//test用户对所有数据库拥有所有权力,并且要求ssl加密
grant all privileges on *.* to 'test'@'%' identified by '123456' require ssl
当添加完用户后,别忘 了 flush privileges;
二,删除用户
语法:
DROP USER user [, user] ...
实例:
drop user 'test2'@'localhost'; //当用drop删除用户进,tables_priv,procs_priv等表中的数据也会被删除
在这里为什么要用'test2'@'localhost'当用户名,而不是直接test2呢,因为mysql.user这张表,是根用户名和host名决定一个用户,你可查看一下表结构就知道了。
show create table mysql.user/G;你会发现有这个东西PRIMARY KEY (`Host`,`User`),表示联合主键
三,修改用户
语法:
RENAME USER old_user TO new_user
[, old_user TO new_user] ...
实例:
rename user 'test2'@'localhost' to 'test'@'%';
四,修改权限
语法:
REVOKE
priv_type [(column_list)]
[, priv_type [(column_list)]] ...
ON [object_type] priv_level
FROM user [, user] ...
REVOKE ALL PRIVILEGES, GRANT OPTION
FROM user [, user] ...
grant就给用户分配权限,revoke是把权限从用户的身上拿走。
实例:
mysql> revoke update on *.* from 'tank'@'localhost';
Query OK, 0 rows affected (0.00 sec)
mysql> select mysql.user.update_priv from mysql.user where user='tank' and host='localhost';
+-------------+
| update_priv |
+-------------+
+-------------+
1 row in set (0.00 sec)
去掉tank@localhost这个用户的更新功能,这个是去掉一个权限,如果我要全部去掉怎么办呢,一个一个写太麻烦了,看下面的一个例子
mysql> revoke all privileges ,grant option from '33'@'localhost';
Query OK, 0 rows affected (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)
用掉33@localhost这个用户的所有权限
作者:海底苍鹰bitsCN.com

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