SQL-DATABASE ERROR

Database error in WoltLab Burning Board (): Link-ID == false, connect failed
mysql error: Too many connections
mysql error number: 1040
mysql version: unknown
php version: 5.4.45
Date: 23.04.2018 @ 03:53
Script: /thread.php?threadid=4495&sid=97ef4f17b0bd4acaedaf2588a8a7f7cb
Referer: