Home Database Mysql Tutorial mysql数据库中的information_schema和mysql可以删除吗?_MySQL

mysql数据库中的information_schema和mysql可以删除吗?_MySQL

Jun 01, 2016 pm 01:12 PM
mysql information Database systems

新装的mysql里面有两个数据库:information_schema 和 mysql  。他们是干么用的?可以删除么?
当然是不可以删除的。

1.information schema 是mysql系统用的所有字典信息,包括数据库系统有什么库,有什么表,有什么字典,有什么存储过程等所有对象信息和进程访问、状态信息。
一旦删除该数据库系统将无法使用。

2.mysql数据库是保存系统有关的权限,对象和状态信息。同样是不能删除的。
并且这两个数据库都很小,不占用空间,你为什么要删除呢。?

mysql数据库中的 information_schema (17)是个什么啊?可以删掉吗?如果删除了会怎么样?比如一个cms程序用的是php+mysql数据库,如果在安装cms程序之前 删除了information_schema (17)那么,在安装程序的过程中,会自动创建吗?谢谢

如果按网上或书上的解释,可能你很难理解过来information_schema是什么东西,网上和书上的解释都是废话,无非你抄我,我抄你。

说得简单点,information_schema这张数据表保存了MySQL服务器所有数据库的信息。如数据库名,数据库的表,表栏的数据类型与访问权限等。再简单点,这台MySQL服务器上,到底有哪些数据库、各个数据库有哪些表,每张表的字段类型是什么,各个数据库要什么权限才能访问,等等信息都保存在information_schema表里面。

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