1. 授予权限：

GRANT privilege[, privilege...]

TO user [, user| role, PUBLIC...];

①DBA授予用户系统权限

GRANT create session, create table,

create sequence, create view

TO LGR;

②创建角色并授权

SYS@LGR> create role manager;  

Role created.       --创建manager角色

SYS@LGR> grant create table,create view to manager; 

Grant succeeded.    --授权给manager

SYS@LGR> grant manager to LGR;

Grant succeeded.    --把manager角色授予LGR用户

③授予对象权限

GRANT select on employees

TO LGR;

④授予指定的列给用户和角色

GRANT update (department_name, location_id)

on departments

TO LGR, manager;

⑤WITH GRANT OPTION 使用户同样具有分配权限的权利

GRANT select, insert

on departments

TO LGR

WITH GRANT OPTION;

⑥向数据库中所有用户分配权限

GRANT select

on hr.employees

TO PUBLIC;

2.确认授予的权限

3.撤销对象权限
•使用REVOKE语句撤销权限
•使用WITH GRANT OPTION 子句所分配的权限同样被收回

REVOKE {privilege [, privilege...]|ALL}

ONobject

FROM {user[, user...]|role|PUBLIC}

[CASCADE CONSTRAINTS];

例如：撤销授予给LGR 用户EMP表的SELECT 和INSERT 权限。

revoke select,insert on EMP from LGR;