1.首先查看表空间的名字和所属文件

select tablespace_name, file_id, file_name,
round(bytes/(1024*1024),0) total_space
from dba_data_files
order by tablespace_name;

     2.增加数据文件 alter tablespace users add datafile '/u01/Oracle/oradata/umail/users02.dbf' size 4000M autoextend off;
alter database datafile '/u01/oracle/oradata/umail/user01.dbf' autoextend off; 

    3.设定后查看表空间信息

SELECT A.TABLESPACE_NAME,A.BYTES TOTAL,B.BYTES USED, C.BYTES FREE,
(B.BYTES*100)/A.BYTES "% USED",(C.BYTES*100)/A.BYTES "% FREE"
FROM SYS.SM$TS_AVAIL A,SYS.SM$TS_USED B,SYS.SM$TS_FREE C
WHERE A.TABLESPACE_NAME=B.TABLESPACE_NAME AND A.TABLESPACE_NAME=C.TABLESPACE_NAME;