title: Invalid common user or role name
body: <p>why is this showing error..</p>
  
  <pre><code>SQL&gt; create user nisar identified by kk ;
  create user nisar identified by kk
              *
  </code></pre>
  
  <blockquote>
    <p>ERROR at line 1:</p>
    
    <p>ORA-65096: invalid common user or role name</p>
  </blockquote>