Warning: mysqli_connect(): (HY000/2002): No such file or directory in /usr/share/nginx/html/kanrigamen/connect_sql.php on line 3

Fatal error: Uncaught ArgumentCountError: mysqli_error() expects exactly 1 argument, 0 given in /usr/share/nginx/html/kanrigamen/connect_sql.php:3 Stack trace: #0 /usr/share/nginx/html/kanrigamen/connect_sql.php(3): mysqli_error() #1 /usr/share/nginx/html/index.php(3): require('...') #2 {main} thrown in /usr/share/nginx/html/kanrigamen/connect_sql.php on line 3