概述

在数据库系统中，除了需要对于用户或角色进行权限授予，还需根据实际情况对其进行权限回收。权限回收的语法格式与权限授予一一匹配，在权限回收时仅需将权限授予的关键字GRANT TO改为 REVOKE FROM即可。

同理，权限回收也可包括：库级权限回收、模式级权限回收、对象级权限回收与列级权限回收。

说明：

权限回收在执行后立即生效。

语法格式

RevokeStmt::=
    REVOKE privileges ON name_space FROM grantee_list
|   REVOKE privileges ON {TABLE | VIEW | PROCEDURE | PACKAGE | SEQUENCE} name_space FROM grantee_list
|   REVOKE GRANT OPTION FOR privileges ON name_space FROM grantee_list
|   REVOKE GRANT OPTION FOR sys_privileges FROM grantee_list
|   REVOKE GRANT OPTION FOR sys_privileges IN SCHEMA name FROM grantee_list
|   REVOKE GRANT OPTION FOR operation_commalist ( name_list ) ON name_space FROM grantee_list
|   REVOKE sys_privileges FROM grantee_list
|   REVOKE sys_privileges IN SCHEMA name FROM grantee_list
|   REVOKE operation_commalist ( name_list ) ON name_space FROM grantee_list
|   REVOKE operation_commalist ( name_list ) ON TABLE name_space FROM grantee_list