n.表空间
Recovering from the loss of a data file that belongs to a traditional rollback segment tablespace. 从属于传统回滚段表空间的数据文件的丢失中恢复。
All objects subsequently created within the tablespace will be stored in files underneath this directory. 所有随后在该表空间创建的对象都将被存放在这个目录下的文件里。
