数据库连接出错，错误信息：php_network_getaddresses: getaddrinfo failed: Name or service not known
Fatal error: Uncaught Error: Call to a member function fetch_array() on null in /var/www/html/jbuy_com_au/public_html/public/function_sql.php:1591
Stack trace:
#0 /var/www/html/jbuy_com_au/public_html/mall/call/list_sql.php(60): SmallClassID(0)
#1 /var/www/html/jbuy_com_au/public_html/mall/list.php(16): require_once('/var/www/html/j...')
#2 {main}
thrown in /var/www/html/jbuy_com_au/public_html/public/function_sql.php on line 1591