SQL> SQL> SQL> select owner, tablespace_name, sum(bytes)/(1024*1024) total_meg 2 from dba_extents 3 where rownum < 50 4 group by rollup (owner,tablespace_name) 5 / OWNER TABLESPACE_NAME TOTAL_MEG ------------------------------ ------------------------------ ---------- SYS SYSTEM 4 SYS 4 4 SQL>