Connection failed: SQLSTATE[HY000] [2002] Connection refused<br />
<b>Fatal error</b>:  Uncaught Error: Call to a member function query() on null in /www/wwwroot/patent.qingtingyigo.com/inc/coon.php:19
Stack trace:
#0 /www/wwwroot/patent.qingtingyigo.com/list.php(2): require_once()
#1 {main}
  thrown in <b>/www/wwwroot/patent.qingtingyigo.com/inc/coon.php</b> on line <b>19</b><br />