oracle 查看对象空间信息

--1、表空间大小
-- 估算1
Select Tablespace_Name, Sum(bytes) / 1024 / 1024
  From Dba_Segments
 Group By Tablespace_Name
 order by Sum(bytes) / 1024 / 1024 desc;
 
--2、表占用空间
select segment_name, sum(bytes) / 1024 / 1024 Mbytese
  from user_segments
 where segment_type = 'TABLE'
 group by segment_name
 order by segment_name;
Select Segment_Name, Sum(bytes) / 1024 / 1024
  From User_Extents
 Group By Segment_Name
 order by Sum(bytes) / 1024 / 1024 desc;

--3、索引占用空间
select segment_name, sum(bytes) / 1024 / 1024 Mbytese
  from user_segments
 where segment_type = 'INDEX'
 group by segment_name
 order by segment_name;

--4、数据文件使用情况
select a.tablespace_name,
       round(a.bytes / 1024 / 1024, 0) "总空间",
       round((decode(b.bytes, null, 0, b.bytes)) / 1024 / 1024, 0) "使用空间",
       round((decode(b.bytes, null, 0, b.bytes)) / a.bytes * 100, 1) "使用率",
       c.file_name,
       c.status
  from sys.sm$ts_avail a, sys.sm$ts_free b, dba_data_files c
 where a.tablespace_name = b.tablespace_name(+)
   and a.tablespace_name = c.tablespace_name
 order by a.tablespace_name;

---使用情况2
select b.file_id 文件ID,
       b.tablespace_name 表空间,
       b.file_name 物理文件名,
       b.bytes / 1024 / 1024 大小M,
       c.max_extents / 1024 / 1024 可扩展数M,
       b.bytes / 1024 / 1024 + c.max_extents / 1024 / 1024 总大小M,
       trunc((b.bytes - sum(nvl(a.bytes, 0))) / 1024 / 1024) 　已使用M,
       trunc(sum(nvl(a.bytes, 0)) / 1024 / 1024) 　剩余M,
       trunc(sum(nvl(a.bytes, 0)) / (b.bytes) * 100, 2) 　剩余比
  from dba_free_space a, dba_data_files b, dba_tablespaces c
 where a.file_id = b.file_id
   and b.tablespace_name = c.tablespace_name
 group by b.tablespace_name,
          b.file_name,
          b.file_id,
          b.bytes,
          c.max_extents,
          b.bytes / 1024 / 1024 + c.max_extents / 1024 / 1024
 order by b.file_id;

--5、表空间使用统计
  select a.tablespace_name,
         a.bytes / 1024 / 1024 "Sum MB",
         (a.bytes - b.bytes) / 1024 / 1024 "used MB",
         b.bytes / 1024 / 1024 "free MB",
         round(((a.bytes - b.bytes) / a.bytes) * 100, 2) "percent_used"
    from (select tablespace_name, sum(bytes) bytes
            from dba_data_files
           group by tablespace_name) a,
         (select tablespace_name, sum(bytes) bytes, max(bytes) largest
            from dba_free_space
           group by tablespace_name) b
   where a.tablespace_name = b.tablespace_name
   order by ((a.bytes - b.bytes) / a.bytes) desc;
--表空间大小估算2
select a.tablespace_name,
       round(a.s,2) "CURRENT_TOTAL(MB)",
       round((a.s - f.s),2) "USED(MB)",
       f.s "FREE(MB)",
       round(f.s / a.s * 100, 2) "FREE%",
       g.autoextensible,
       round(a.ms,2) "MAX_TOTAL(MB)"
  from (select d.tablespace_name,
               sum(bytes / 1024 / 1024) s,
               sum(decode(maxbytes, 0, bytes, maxbytes) / 1024 / 1024) ms
          from dba_data_files d
         group by d.tablespace_name) a,
       (select f.tablespace_name, sum(f.bytes / 1024 / 1024) s
          from dba_free_space f
         group by f.tablespace_name) f,
       (select distinct tablespace_name, autoextensible
          from DBA_DATA_FILES
         where autoextensible = 'YES'
        union
        select distinct tablespace_name, autoextensible
          from DBA_DATA_FILES
         where autoextensible = 'NO'
           and tablespace_name not in
               (select distinct tablespace_name
                  from DBA_DATA_FILES
                 where autoextensible = 'YES')) g
 where a.tablespace_name = f.tablespace_name
   and g.tablespace_name = f.tablespace_name order by "FREE%";

--准确计算表空间大小
SELECT F.TABLESPACE_NAME,
       A.ALL_TOTAL "总空间",
       A.ALL_USED "总使用空间",
       A.ALL_TOTAL - A.ALL_USED "总剩余空间",
       (A.ALL_TOTAL - A.ALL_USED) / A.ALL_TOTAL * 100 "总剩余比例",
       A.TOTAL "当前大小",
       U.USED "当前使用空间",
       F.FREE "当前剩余空间",
       (U.USED / A.TOTAL) * 100"当前使用比例",
       (F.FREE / A.TOTAL) * 100 "当前剩余比例"
  FROM (SELECT TABLESPACE_NAME,
               SUM(BYTES / (1024 * 1024 * 1024)) TOTAL,
               SUM(DECODE(AUTOEXTENSIBLE, 'YES', MAXBYTES, BYTES) /
                   (1024 * 1024 * 1024)) ALL_TOTAL,
               SUM(USER_BYTES) / (1024 * 1024 * 1024) ALL_USED
          FROM DBA_DATA_FILES
         GROUP BY TABLESPACE_NAME) A,
       (SELECT TABLESPACE_NAME, SUM(BYTES / (1024 * 1024 * 1024)) USED
          FROM DBA_EXTENTS
         GROUP BY TABLESPACE_NAME) U,
       (SELECT TABLESPACE_NAME, SUM(BYTES / (1024 * 1024 * 1024)) FREE
          FROM DBA_FREE_SPACE
         GROUP BY TABLESPACE_NAME) F
 WHERE A.TABLESPACE_NAME = F.TABLESPACE_NAME(+)
   AND A.TABLESPACE_NAME = U.TABLESPACE_NAME(+)
 ORDER BY (A.ALL_TOTAL - A.ALL_USED) / A.ALL_TOTAL,F.FREE / A.TOTAL ASC;

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