directory 用途 数据泵 导入、导出
1、查询directory目录
select * from dba_directories;
2、创建或者修改 directory目录
create or replace directory dum_date_dir as '/home/oracle/datatmp'
3、赋权 directory目录
grant read,write on directory dumpdir to username;
4、删除directory目录
drop directory DIRENAME;