title: Change NLS Character set parameters on Oracle 11g XE
body: <p>I am using Oracle 11g Express Edition. Currently when I check NLS character set parameter using <code>SELECT * FROM nls_database_parameters;</code> it gives the default values:</p>
  
  <pre><code>NLS_CHARACTERSET: AL32UTF8
  NLS_NCHAR_CHARACTERSET: AL16UTF16
  </code></pre>
  
  <p>I want to set both these parameters to UTF8. How can I do so? I have just installed Oracle 11g XE, so there is not data except those required by Oracle itself.</p>