删除页面中显示的mysqli_connect警告

$mysqlServer = "***";
$mysqlDb = "***";
$mysqlUser = "***";
$mysqlPass = "***";
$conn = mysqli_connect($mysqlServer, $mysqlUser, $mysqlPass) or die("failed to connect to db");
mysqli_select_db($conn, $mysqlDb) or die("failed to connect select db");

我有这个代码，它的工作没有任何问题。但如果我试图输入一个错误的sql服务器或测试它执行一个错误。这将显示:

Warning: mysqli_connect(): (HY000/2002): A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.
failed to connect select db

我不希望在连接SQL服务器时显示警告。我只想显示我自己的错误

$conn = @mysqli_connect($mysqlServer, $mysqlUser, $mysqlPass) or die("failed to connect to db");

$conn = mysqli_connect($mysqlServer, $mysqlUser, $mysqlPass, $mysqlDb);