查询表空间使用率（自动扩展的也能查噢）

col tablespace_name for a40
col CUR_PCT for a10
col EXT_PCT for a10
select 
tablespace,
current_used_mb,
total_mb,
can_extend_mb,
trunc(current_used_mb/total_mb*100,2)||'%' cur_pct,
trunc(current_used_mb/can_extend_mb*100,2)||'%' ext_pct,
count_file
from
(select
a.tablespace_name tablespace,
trunc((b.total-a.free)/1024/1024,2) current_used_mb,
trunc(b.total/1024/1024,2) total_mb,
trunc(b.extent_total/1024/1024) can_extend_mb,
b.count_file count_file
from
(select 
tablespace_name,
sum(bytes) free
from dba_free_space
group by tablespace_name) a,　　
(select tablespace_name,                                         
sum(nvl(bytes,0)) total,                       
sum(decode(maxbytes,0,bytes,maxbytes)) extent_total,       
count(file_name) count_file                                    
from dba_data_files                                           
group by tablespace_name) b
where a.tablespace_name=b.tablespace_name);