[size=large][b][color=darkred]select a.tablespace_name,
a.bytes bytes_used,
b.free_largest,
round(((a.bytes - b.bytes) / a.bytes) * 100, 2) percent_used
from (select tablespace_name, sum(bytes) bytes
from dba_data_files
group by tablespace_name) a,
(select tablespace_name, sum(bytes) bytes, max(bytes) free_largest
from dba_free_space
group by tablespace_name) b
where a.tablespace_name = b.tablespace_name
order by ((a.bytes - b.bytes) / a.bytes) desc[/color][/b][/size]