Oracle常用查询表空间的操作

查看表空间离不开一般需求是查看表空间的名字，大小，使用率和空闲大小

一般最常见的表就是 dba_tablespaces,dba_data_files,dba_free_space,dba_temp_files,dba_temp_free_space;
经总结和借鉴，常用的sql语句如下

1.  查看表空间总大小（包含temp表空间）
select * from ( 
      Select a.tablespace_name "表空间名", 
             to_char(a.bytes/1024/1024,'99,999.99') "表空间大小(M)", 
             to_char(b.bytes/1024/1024,'99,999.99') "剩余空间大小(M)", 
             to_char(a.bytes/1024/1024 - b.bytes/1024/1024,'99,999.99') "使用空间大小(M)", 
             to_char((1 - b.bytes/a.bytes)*100,'99.99') || '%' "使用比" 
      from (select tablespace_name, 
                   sum(bytes) bytes 
            from dba_data_files 
            group by tablespace_name) a, 
                     (select tablespace_name , 
                             sum(bytes) bytes 
                      from dba_free_space 
                      group by tablespace_name) b 
                      where a.tablespace_name = b.tablespace_name 
      union all 
      select c.tablespace_name "表空间名", 
             to_char(c.bytes/1024/1024,'99,999.99') "表空间大小(M)", 
             to_char( (c.bytes-d.bytes_used)/1024/1024,'99,999.99') "剩余空间大小(M)", 
             to_char(d.bytes_used/1024/1024,'99,999.99') "使用空间大小(M)", 
             to_char(d.bytes_used*100/c.bytes,'99.99') || '%' "使用比" 
      from 
             (select tablespace_name ,sum(bytes) bytes 
              from dba_temp_files group by tablespace_name) c, 
             (select tablespace_name,sum(bytes_cached) bytes_used 
              from v$temp_extent_pool group by tablespace_name) d 
      where c.tablespace_name = d.tablespace_name 
);

2.查看表空间所属的数据文件及是否可自动扩展
select file_name,tablespace_name,autoextensible from dba_data_files;

3.查看各用户拥有的表空间大小

select owner,tablespace_name ,sum(bytes)/1024/1024 from dba_segments where owner='SYS' group by owner,tablespace_name;