현재 사용량
select sum(bytes)/1024/1024/1024 GB from dba_segments;
오라클에 잡혀있는용량
select sum(bytes)/1024/1024/1024 GB from dba_data_files;
select sum(bytes)/1024/1024/1024 GB from dba_segments;
select sum(bytes)/1024/1024/1024 GB from dba_data_files;