Oracle 查询表空间的存储大小和已使用率

select tablespace_name,       max_gb,       used_gb,       round(100 * used_gb / max_gb) pct_used  from (select a.tablespace_name tablespace_name,               round((a.bytes_alloc - nvl(b.bytes_free, 0)) / power(2, 30),                     2) used_gb,               round(a.maxbytes / power(2, 30), 2) max_gb          from (select f.tablespace_name,                       sum(f.bytes) bytes_alloc,                       sum(decode(f.autoextensible,                                  'YES',                                  f.maxbytes,                                  'NO',                                  f.bytes)) maxbytes                  from dba_data_files f                 group by tablespace_name) a,               (select f.tablespace_name, sum(f.bytes) bytes_free                  from dba_free_space f                 group by tablespace_name) b         where a.tablespace_name = b.tablespace_name(+)        union all        select h.tablespace_name tablespace_name,               round(sum(nvl(p.bytes_used, 0)) / power(2, 30), 2) used_gb,               round(sum(decode(f.autoextensible,                                'YES',                                f.maxbytes,                                'NO',                                f.bytes)) / power(2, 30),                     2) max_gb          from v$temp_space_header h, v$temp_extent_pool p, dba_temp_files f         where p.file_id(+) = h.file_id           and p.tablespace_name(+) = h.tablespace_name           and f.file_id = h.file_id           and f.tablespace_name = h.tablespace_name         group by h.tablespace_name)order by 4;