Get the Temporary Table Space information?

Solution:

select (select sum(Bytes)/1024/1024/1024 from dba_temp_files) "TOTAL SPACE in GB",(select decode(sum(blocks),null,0,sum(blocks)*8192/1024/1024/1024) from v$sort_usage) "CURRENT USAGE in GB",(select count(*) from v$sort_usage where blocks>(100000000/8192))"SESSIONS USING > 1000MB" from dual;

or

SELECT inst_id "instid",
SUBSTR(tablespace_name,1,15) "ts",
used_blocks*&bs/1048/1048/1048 "used mb",
free_blocks*&bs/1048/1048/1048 "free mb",
total_blocks*&bs/1048/1048/1048 "total mb"
FROM gv$sort_segment;

(pass block_size(get it from show parameter block_size))