TEMP tablespace usage

Temporary Segments in Database
SELECT A.tablespace_name tablespace, D.mb_total,SUM (A.used_blocks * D.block_size) / 1024 / 1024 mb_used,D.mb_total - SUM (A.used_blocks * D.block_size) / 1024 / 1024 mb_free FROM v$sort_segment A,(SELECT B.name, C.block_size, SUM(C.bytes) / 1024 / 1024 mb_total FROM v$tablespace B, v$tempfile C WHERE B.ts#= C.ts# GROUP BY B.name, C.block_size) D WHERE A.tablespace_name = D.name GROUP by A.tablespace_name, D.mb_total;

Database Session that is using space in a sort segment

SELECT   S.sid || ',' || S.serial# sid_serial, S.username, S.osuser, P.spid, S.module,S.program,SUM (T.blocks) * TBS.block_size / 1024 / 1024 mb_used, T.tablespace,COUNT(*) sort_ops FROM     v$sort_usage T, v$session S, dba_tablespaces TBS, v$process P WHERE    T.session_addr = S.saddr AND S.paddr = P.addr AND T.tablespace = TBS.tablespace_name GROUP BY S.sid, S.serial#, S.username, S.osuser, P.spid, S.module,S.program, 
TBS.block_size, T.tablespace ORDER BY sid_serial;
Sort Space Usage by Statement
SELECT   S.sid || ',' || S.serial# sid_serial, S.username, T.blocks * TBS.block_size / 1024 / 1024 mb_used,  T.tablespace,T.sqladdr address, Q.hash_value, Q.sql_text  FROM v$sort_usage T, v$session S, v$sqlarea Q, dba_tablespaces TBS WHERE T.session_addr = S.saddr AND T.sqladdr = Q.address (+) AND T.tablespace = TBS.tablespace_name ORDER BY S.sid;