Note:
You cannot take a temporary tablespace offline. Instead, you take its tempfile offline.
The following statement take tempfile offline.
SQL> ALTER DATABASE TEMPFILE '<path_and_file_name>' OFFLINE;
Example:
SQL> ALTER DATABASE TEMPFILE '/u01/oradata/ORCL10G/temp01.dbf' OFFLINE;
Database altered.
SQL>
To display the status for a tempfile.
col name for a35
select NAME, STATUS from V$TEMPFILE;
SQL> col name for a35
select NAME, STATUS from V$TEMPFILE;SQL>
NAME STATUS
----------------------------------- -------
/u01/oradata/ORCL10G/temp01.dbf OFFLINE
SQL>