查询表空间的总容量
SQL> select tablespace_name, sum(bytes)/1024/1024 as MB from dba_data_files group by
tablespace_name;
未使用的表空间大小
SQL> select tablespace_name,sum(bytes)/1024/1024 from dba_free_space   
group by tablespace_name;
查询表空间使用率
  1. SQL> select  
  2. total.tablespace_name,   
  3. round(total.MB,2) as Total_MB,   
  4. round(total.MB-free.MB, 2) as Used_MB,   
  5. 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,   
  6. (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;  

转完内容了小提示：连接的数据库的要是sys用户或者有dba权限的用户才可查看