oracle8、 查看每个表空间总大小，空闲多少，空闲百分比，使用百分比

1、 查看每个表占用空间大小1
select segment_name,sum(bytes)/1024/1024 from user_extents group by segment_name;
2、 查看每个表占用空间大小2
select segment_name,sum(bytes)/1024/1024 from user_segments where segment_type='TABLE' group by segment_name;
3、 查看用户表,索引,分区表占用空间
select segment_name,sum(bytes)/1024/1024 from user_segments group by segment_name;
4、 查看每索引占用空间大小
select segment_name,sum(bytes)/1024/1024 from user_segments where segment_type='INDEX' group by segment_name;
5、 查看每个表占用空间大小,按大小排序，只显示最前面9条
select * from (select segment_name,sum(bytes)/1024/1024 coun from user_extents group by segment_name order by  coun desc) where rownum<10;
6、 查看每个表空间占用大小
select tablespace_name,sum(bytes)/1024/1024 from dba_segments group by tablespace_name;


7、 查看某个表空间下每个表占用空间大小
select blocks*8192/1024/1024,table_name from dba_tables where tablespace_name='CBS_LOG_DAT' order by blocks desc;

8、 查看每个表空间总大小，空闲多少，空闲百分比，使用百分比
SELECT DF.TABLESPACE_NAME "Tablespace",                          
       DF.BYTES / (1024 * 1024) "Total Size(MB)",                
       SUM(FS.BYTES) / (1024 * 1024) "Free Size(MB)",            
       ROUND(SUM(FS.BYTES) * 100 / DF.BYTES) "% Free",           
       ROUND((DF.BYTES - SUM(FS.BYTES)) * 100 / DF.BYTES) "% Used"
  FROM DBA_FREE_SPACE FS,                                        
       (SELECT TABLESPACE_NAME, SUM(BYTES) BYTES                 
          FROM DBA_DATA_FILES                                    
         GROUP BY TABLESPACE_NAME) DF                            
WHERE FS.TABLESPACE_NAME = DF.TABLESPACE_NAME                   
GROUP BY DF.TABLESPACE_NAME, DF.BYTES;