I have mistakenly deleted Datafiles. In my production server I have mistakenly deleted datafiles. When I am trying to open the database I am getting an error. The files are not important but the database is not opening up. 

SQL&gt; alter database open;
alter database open
*
ERROR at line 1:
ORA-01589: must use RESETLOGS or NORESETLOGS option for database open
SQL&gt;  alter database open RESETLOGS;
alter database open RESETLOGS
*
ERROR at line 1:
ORA-01194: file 1 needs more recovery to be consistent
ORA-01110: data file 1: '/u01/mars/oradata/MARS/system01.dbf'


I have tried plenty of ways to recover but it is not opening. 
LIKE

SQL&gt; recover database until cancel;
ORA-00283: recovery session canceled due to errors
ORA-01610: recovery using the BACKUP CONTROLFILE option must be done

RECOVER DATABASE USING BACKUP CONTROLFILE UNTIL CANCEL ;
ORA-00283: recovery session canceled due to errors
ORA-01110: data file 5: '/u01/mars/oradata/MARS/example01.dbf'
ORA-01157: cannot identify/lock data file 5 - see DBWR trace file
ORA-01110: data file 5: '/u01/mars/oradata/MARS/example01.dbf'
Since you don't care about the data, you can try the following which will offline and drop the datafile in question allowing you to open the database.

SQL&gt; startup
ORACLE instance started.

Total System Global Area 1720328192 bytes
Fixed Size                  2255904 bytes
Variable Size            1275069408 bytes
Database Buffers          436207616 bytes
Redo Buffers                6795264 bytes
Database mounted.
ORA-01157: cannot identify/lock data file 6 - see DBWR trace file
ORA-01110: data file 6: 'C:\ORACLE\ORADATA\ORCL\TRASHED01.DBF'

SQL&gt; alter database datafile 6 offline drop;

Database altered.

SQL&gt; alter database open;

Database altered.

SQL&gt;