Oracle : Start Database in No archive log mode.

SQL> archive log list
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            /opt/app/dbname/oraflsh01/archivelog
Oldest online log sequence     9
Next log sequence to archive   34
Current log sequence           34

SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.

SQL> startup mount
ORACLE instance started.

Total System Global Area 5.9861E+10 bytes
Fixed Size                  2267792 bytes
Variable Size            1.0737E+10 bytes
Database Buffers         4.8989E+10 bytes
Redo Buffers              131936256 bytes
Database mounted.

SQL> alter database noarchivelog;

Database altered.

SQL> alter database open;

Database altered.

SQL> archive log list
Database log mode              No Archive Mode
Automatic archival             Disabled
Archive destination            /opt/app/dbname/oraflsh01/archivelog
Oldest online log sequence     9
Current log sequence           34