Warning: mysqli_query() expects at least 2 parameters, 1 is given in..

Question

I can't figure out on where I get the error on lines 05 and 06. Please help.

<?php
$config=mysqli_connect("localhost","root","");
mysqli_select_db($config,"dk");
   function register($id,$uname,$pass){
             $q="insert into users values ('$id','$uname','$pass')";
             mysqli_query("alter table users auto_increment = 1");
             if(mysqli_query($q)){
                 mkdir("$dir", 0700);
                 echo "<script language='javascript'>
    alert('User Registered');
    window.location = 'administrator.php';
    </script>
    ";

             }
             else{
                  echo "<script language='javascript'>
    alert('Registration Failed Or User Already Registered');
    window.location = 'administrator.php';
    </script>
    ";
             }
         }
?>