title: How to change character set after installation of Oracle 11.2 in Windows 10?
body: <p>I have installed Oracle 11.2.0.1.0 in Windows 10 pro for testing and learning. 
  The <code>NLS_CHARACTERSET</code> is <code>WE8MSWIN1252</code> but I need it to be <code>AL32UTF8</code>.
  How can I change the characterset after installation of Oracle 11.2 in Windows 10?</p>