Hi

I found this code in internet, and i want to used it , but my database is mysql not mysqli, how can I change my syntax.

PHP Code:
<?php    $db = new mysqli('DB_HOST''USERNAME' ,'PASSWORD''DATABASE_NAME');
       if(!
$db) {     
      echo 
'Could not connect to the database.'
    } else {   
        if(isset(
$_POST['queryString'])) {  
           
$queryString $db->real_escape_string($_POST['queryString']);   
            if(
strlen($queryString) >0) {         
          
$query $db->query("SELECT country FROM countries WHERE country LIKE '$queryString%' LIMIT 10");   
              if(
$query) {  
               echo 
'<ul>';               
      while (
$result $query ->fetch_object()) {      
                   echo 
'<li onClick="fill(\''.addslashes($result->country).'\');">'.$result->country.'</li>';              
       }               
  echo 
'</ul>';                 
  } else {                 
    echo 
'OOPS we had a problem <IMG class=wp-smiley alt=:( src="http://www.wavesdream.com/wp-includes/images/smilies/icon_sad.gif"> ';        
         }           
  } else {     
            
// do nothing        
     
}       
  } else {          
   echo 
'There should be no direct access to this script!';   
      }    
 } 
?>
Thank you