如何查看oracle用戶具有的權限和角色

查看用戶或角色系統權限
select * from dba_sys_privs;
select * from user_sys_privs;
查看用戶對象權限
select * from dba_tab_privs;
select * from all_tab_privs;
select * from user_tab_privs;
查看所有角色
select * from dba_roles;
查看用戶或角色所擁有的角色：
select * from dba_role_privs;
select * from user_role_privs;