--查询表空间使用情况
SELECT Upper(F.TABLESPACE_NAME)         "表空间名",D.TOT_GROOTTE_MB                 "表空间大小(M)",D.TOT_GROOTTE_MB - F.TOTAL_BYTES "已使用空间(M)",To_char(Round(( D.TOT_GROOTTE_MB - F.TOTAL_BYTES ) / D.TOT_GROOTTE_MB * 100,2),'990.99')
       || '%'                           "使用比",F.TOTAL_BYTES                    "空闲空间(M)",F.MAX_BYTES                      "最大块(M)"
FROM   (SELECT TABLESPACE_NAME,Round(Sum(BYTES) / ( 1024 * 1024 ),2) TOTAL_BYTES,Round(Max(BYTES) / ( 1024 * 1024 ),2) MAX_BYTES
        FROM   SYS.DBA_FREE_SPACE
        GROUP  BY TABLESPACE_NAME) F,(SELECT DD.TABLESPACE_NAME,Round(Sum(DD.BYTES) / ( 1024 * 1024 ),2) TOT_GROOTTE_MB
        FROM   SYS.DBA_DATA_FILES DD
        GROUP  BY DD.TABLESPACE_NAME) D
WHERE  D.TABLESPACE_NAME = F.TABLESPACE_NAME
ORDER  BY 1
 
--查询表空间的free space
select tablespace_name,count(*) AS extends,round(sum(bytes) / 1024 / 1024,2) AS MB,sum(blocks) AS blocks from dba_free_space group BY tablespace_name;
 
--查询表空间的总容量
select tablespace_name,sum(bytes) / 1024 / 1024 as MB from dba_data_files group by tablespace_name;
--查询表空间使用率
SELECT total.tablespace_name,Round(total.MB,2)           AS Total_MB,Round(total.MB - free.MB,2) AS Used_MB,Round(( 1 - free.MB / total.MB ) * 100,2)
       || '%'                       AS Used_Pct
FROM   (SELECT tablespace_name,Sum(bytes) / 1024 / 1024 AS MB
        FROM   dba_free_space
        GROUP  BY tablespace_name) free,(SELECT tablespace_name,Sum(bytes) / 1024 / 1024 AS MB
        FROM   dba_data_files
        GROUP  BY tablespace_name) total
WHERE  free.tablespace_name = total.tablespace_name;