表領域の空き領域とサイズを調べる

SELECT tablespace_name　"表領域名", SUM(bytes)/1024/1024 "空き領域(MB)"
 FROM dba_free_space GROUP BY tablespace_name;
SELECT tablespace_name　"表領域名", SUM(bytes)/1024/1024 "サイズ(MB)"
 FROM dba_data_files GROUP BY tablespace_name;