Erro na conexão com o banco de dados: SQLSTATE[HY000] [2002] Connection refused<br />
<b>Warning</b>:  Undefined variable $pdo in <b>/var/www/html/topico.php</b> on line <b>21</b><br />
<br />
<b>Fatal error</b>:  Uncaught Error: Call to a member function query() on null in /var/www/html/topico.php:21
Stack trace:
#0 {main}
  thrown in <b>/var/www/html/topico.php</b> on line <b>21</b><br />