mysql数据库权限更改后的生效时间_MySQL
When Privilege Changes Take Effect
1.当mysqld启动时,所有授权表的内容被读进内存并且从此时生效。
2.当服务器注意到授权表被改变了时,现存的客户端连接有如下影响:
表和列权限在客户端的下一次请求时生效。
数据库权限改变在下一个USE db_name命令生效。
全局权限的改变和密码改变在下一次客户端连接时生效。
3.如果用GRANT、REVOKE或SET PASSWORD对授权表进行修改,服务器会注意到并立即重新将授权表载入内存。
4.如果你手动地修改授权表(使用INSERT、UPDATE或DELETE等等),你应该执行mysqladmin flush-privileges或mysqladmin reload告诉服务器再装载授权表,否则你的更改将不会生效,除非你重启服务器。
5.如果你直接更改了授权表但忘记重载,重启服务器后你的更改方生效。这样可能让你迷惑为什么你的更改没有什么变化!

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