RIYOSU

select s.snap_id,s.start_time,s.end_time,x.tablespace_maxsize*x.block_size/1024/1024,
x.tablespace_size*x.block_size/1024/1024,x.tablespace_usedsize*x.block_size/1024/1024
from 
(select dhtsu.snap_id,dhtsu.tablespace_size,dhtsu.tablespace_maxsize,dhtsu.tablespace_usedsize ,dbat.block_size
from DBA_HIST_TBSPC_SPACE_USAGE dhtsu,v$tablespace vt,dba_tablespaces dbat where
dhtsu.tablespace_id = vt.ts# and
vt.name = 'CALYPSO_DATA' and
vt.name = dbat.TABLESPACE_NAME
)x,
( 
select snap_id,
        max(to_char((trunc(begin_interval_time, 'mi')),'DD/MON/YYYY HH24:MI:SS')) as start_time,
        max(to_char((trunc(end_interval_time, 'mi')),'DD/MON/YYYY HH24:MI:SS')) as end_time
        from dba_hist_snapshot
        where begin_interval_time >= sysdate - 30
        group by snap_id
) s
where s.snap_id = x.snap_id
order by snap_id