oracle关于表空间的一些操作

查看 xxx 表空间是否为自动扩展:

select file_name,autoextensible,increment_by from dba_data_files;

select file_id,file_name,tablespace_name,autoextensible,increment_by from dba_data_files order by file_id desc; 

打开表空间自动扩展功能：

alter database datafile '/u01/app/oracle/oradata/testdb/test01.dbf' autoextend on;

查看数据文件大小：

select TABLESPACE_NAME,FILE_NAME,BYTES/1024/1024 M from dba_data_files order 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; 

扩展表空间：

#首先查看表空间的名字和所属文件及空间 

select tablespace_name, file_id, file_name,round(bytes/(1024*1024),0) total_space from dba_data_files order by tablespace_name; 

#三种扩展方法 

1.alter tablespace test add datafile '/u01/test02.dbf' size 10M(自动加一个datafile) 

2.alter database datafile '/u01/test.dbf' resize 20M; 

3.alter database datafile '/u01/test.dbf' autoextend on next 10M maxsize 1G; 

设定后查看表空间信息：

select a.tablespace_name,a.bytes total,b.bytes used,c.bytes free,(b.bytes*100)/a.bytes "% used",(c.bytes*100)/a.bytes "% free" from sys.sm$ts_avail a,sys.sm$ts_used b,sys.sm$ts_free c where a.tablespace_name=b.tablespace_name and a.tablespace_name=c.tablespace_name;