title: ORA 06502 Error PL/SQL
body: <p>I am trying to execute a simple statement and i got an error while executing. </p>
  
  <pre><code>begin
  dbms_output.put_line('Addition: '||4+2);
  end;
  </code></pre>
  
  <blockquote>
    <p>Error:
    ORA-06502: PL/SQL: numeric or value error: character to number conversion error
    ORA-06512: at line 2</p>
  </blockquote>
  
  <p>But when i executed with * operator, it worked fine.</p>
  
  <pre><code>begin
  dbms_output.put_line('Addition: '||4*2);
  end;
  </code></pre>
  
  <p>Does anyone know the reason behind it?</p>