SQLSTATE[HY000] [2002] php_network_getaddresses: getaddrinfo failed: Name or service not known

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#441: /www/wwwweb/wechatapp.jemyh.com/helpers/functions.php
#273: /www/wwwweb/wechatapp.jemyh.com/core/Application.php
#56: /www/wwwweb/wechatapp.jemyh.com/core/WebApplication.php
#16: /www/wwwweb/wechatapp.jemyh.com/web/index.php

Version: 4.5.8