Some basics, right?
Another thing that is not usual and everytime I do, someone be surprised: “shu” alias for “shutdown”:
SQL> create spfile='+DGDATA/MYDB/spfilemydb.ora' from pfile='/oracle/product/11.2/dbs/init_mydb.ora'; File created. SQL> shu immediate; Database closed. Database dismounted. ORACLE instance shut down.
The Bourleson Master also wrote about it. Take a look on a better detailed post about this subject: http://www.dba-oracle.com/concepts/pfile_spfile.htm.