Obtendo informações de Armazenamento no Oracle

Query para Obter informações referentes aos Armazenamento do Oracle:

select
/*+ RULE */ df.tablespace_name, substr(df.file_name,1,4) drive, df.file_id,
round(df.bytes/(1024*1024),0) filesize, round(sum(fs.bytes)/(1024*1024),2) used, decode( sum(fs.bytes), 0, 0, round(100*sum(fs.bytes)/df.bytes,2)) pctused, decode( sign(85-round(100*sum(nvl(fs.bytes,1))/df.bytes,2)),-1,'*','') "%", df.autoextensible,
round(df.maxbytes/(1024*1024),0) maxsize, decode( sign(85-round(100*sum(nvl(fs.bytes,1))/df.maxbytes,2)),-1,'*','') "!", substr(df.file_name, instr(df.file_name,'\',-1)+1, length(df.file_name)) fname_root from dba_data_files df, dba_extents fs
where df.file_id=fs.file_id(+) group by df.tablespace_name, df.file_name, df.file_id, df.bytes, df.autoextensible, df.maxbytes
order by 1,2