依靠dba_hist_tbspc_space_usage视图 获得表空间的每日增长量

select a.name, b.* 
  from v$tablespace a, 
       (select tablespace_id, 
               trunc(to_date(rtime, 'mm/dd/yyyy hh24:mi:ss')) datetime, 
               round(max(tablespace_usedsize * 8 / 1024),2) used_size_MB 
          from dba_hist_tbspc_space_usage 
         where trunc(to_date(rtime, 'mm/dd/yyyy hh24:mi:ss')) > 
               trunc(sysdate - 17) 
         group by tablespace_id, 
                  trunc(to_date(rtime, 'mm/dd/yyyy hh24:mi:ss')) 
         order by tablespace_id, 
                  trunc(to_date(rtime, 'mm/dd/yyyy hh24:mi:ss'))) b 
 where a.ts# = b.tablespace_id; 

转自：http://blog.csdn.net/msdnchina/article/details/38554529