MySQL权限级别_MySQL
MySQL 中的权限分为五个级别,分别如下:
1、Global Level:
Global Level 的权限控制又称为全局权限控制,所有权限信息都保存在mysql.user 表中。
Global Level 的所有权限都是针对整个mysqld 的,对所有的数据库下的所有表及所有字段都有效。
GRANT SELECT,UPDATE,DELETE,INSERT ON *.* TO 'def'@'localhost';
Global Level 主要有如下这些权限(以下为5.0.3以上版本拥有权限)
2、Database Level
Database Level 其作用域即为所指定整个数据库中的所有对象。
GRANT ALTER ON test.* TO 'def'@'localhost';
GRANT DROP ON * TO 'def'@'localhost';
Database Level 主要少了以下几个权限:CREATE USER,FILE,PROCESS,RELOAD,
REPLICATION CLIENT,REPLICATION SLAVE,
SHOW DATABASES,SHUTDOWN,SUPER 和USAGE 这几个权限,没有增加任何权限。
3、Table Level
Table Level 的权限作用范围是授权语句中所指定数据库的指定表。
GRANT INDEX ON test.t1 TO 'abc'@'%.jianzhaoyang.com';
Table Level 的权限由于其作用域仅限于某个特定的表,所以权限种类也比较少,仅有
ALTER,CREATE,DELETE,DROP,INDEX,INSERT,SELECT UPDATE 这八种权限。
4、Column Level
Column Level 的权限作用范围就更小了,仅仅是某个表的指定的某个(活某些)列。
GRANT SELECT(id,value) ON test.t2 TO 'abc'@'%.XXX';
Column Level 级别的权限仅有 INSERT , SELECT 和 UPDATE 这三种。
5、Routine Level
Routine Level 主要针对的对象是procedure 和function 这两种对象,在授予Routine Level 权限的时候,需要指定数据库和相关对象
GRANT EXECUTE ON test.p1 to 'abc'@'localhost';
Routine Level 的权限主要只有EXECUTE 和ALTER ROUTINE 两种

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