无法从SQL PhP获取数据，返回页面无法处理请求

Question

我对PhP很新，我正在尝试建立一个具有权限的员工门户网站。当我尝试从表中获取数据时，页面返回“无法处理此请求”。感谢任何帮助，这是我尝试过的。

<?php
include('./classes/Login.php');
if (Login::isLoggedIn()) {
        $userid = Login::isLoggedIn();
        $staff = "true";
        $con=mysqli_connect("localhost","mqefjvgt_portal","-password sniped-","mqefjvgt_portal");
        $radiodj_query = mysqli_query($con,"SELECT is_radio FROM users_permissions WHERE id=$userid;");
        if ( $radiodj_query == "1" ){
                $radiodj = "true";
                $staff = "true";

        }
        $media_query = mysqli_query($con,"SELECT is_media FROM users_permissions WHERE id=$userid;");
        if ( $media_query == "1" ){
                $media = "true";
                $staff = "true";
        }
        $management_query = mysqli_query($con,"SELECT is_management FROM users_permissions WHERE id=$userid;");
        if ( $management_query == "1" ){
                $management = "true";
                $staff = "true";
        }
        $admin_query = mysqli_query($con,"SELECT is_admin FROM users_permissions WHERE id=$userid;");
        if ( $admin_query == "1" ){
                $admin = "true";
                $staff = "true";
        }
        $owner_query = mysqli_query($con,"SELECT is_owner FROM users_permissions WHERE id=$userid;");
        if ( $owner_query == "1" ){
                $owner = "true";
                $staff = "true";
        }
        echo $owner_query;
        echo $admin_query;
        echo $management_query;
        echo $media_query;
        echo $radiodj_query;
} else {
        echo "<meta http-equiv=\"refresh\" content=\"0;URL='login.php'\" />";
}
?>