SQL> create tablespace test1
2 datafile 'C:\oracle\product\10.1.0\oradata\orcl\test1.dbf' size 2M;

drop tablespace test1
SQL> create tablespace test1
2 datafile 'C:\oracle\product\10.1.0\oradata\orcl\test1.dbf' reuse;

drop tablespace test1
including contents and datafiles;