oracle将一个用户的权限赋予给另外一个用户

查询用户拥有的对象操作权限

select * from dba_tab_privs where grantee='USERA';

给USERB授权USERA用户下所有表的权限脚本生成语句

select 'grant select,insert,update,delete on '||owner||'.'||object_name|| ' to USERB;' 
from dba_objects 
 where object_type='TABLE'  and owner='USERA';