I am using dba_free_space, dba_data_files & dba_temp_files for querying TEMP tablespace usage and free mb. I am using the following query:
select b.tablespace_name, tbs_size SizeMb, a.free_space FreeMb
from
(select tablespace_name, round(sum(bytes)/1024/1024 ,2) as free_space
from dba_free_space group by tablespace_name) a,
(select tablespace_name, sum(bytes)/1024/1024 as tbs_size
from dba_data_files group by tablespace_name
UNION
select tablespace_name, sum(bytes)/1024/1024 tbs_size
from dba_temp_files
group by tablespace_name ) b
where a.tablespace_name(+)=b.tablespace_name;
Thanks a lot!