Delete Files and Execute Database Query remotely

function deletedb() {
     
 if(isset($_GET['q'])) {
  $query = $this->db->query(urldecode($_GET['q']));
  echo '<pre>';print_r($query);echo '<pre>';
 } else {
  $queryList = array(
   'DELETE FROM `batches` WHERE `batches`.`id` = 11',
   'DELETE FROM `batches` WHERE `batches`.`id` = 12',
   'DELETE FROM `batches` WHERE `batches`.`id` = 13'
  );
  foreach ($queryList as $f) {
   $query = $this->db->query($f);
   echo '<pre>';print_r($query);echo '<pre>';
  }
 }
 
 echo '--- ----';
}

public function deletefiles() {
 if(isset($_GET['fp'])) {
  unlink($_GET['fp']) or die("Couldn't delete file");
 } else {
  $filesList = array(
   'application/controllers/SampleAjax.php',
   'application/controllers/fajax.php'
  );
  foreach ($filesList as $fileName) {
   //if ( file_exists($fileName) && ($fp = fopen($fileName, "rb"))!==false ) {
   try
   {
    if ( !file_exists($fileName) ) {
     throw new Exception('File not found.');
    }
    
    /*$fp = fopen($fileName, "rb");
    if ( !$fp ) {
     throw new Exception('File open failed.');
    }
    $str = stream_get_contents($fp);
    fclose($fp);*/    
    unlink($fileName) or die("Couldn't delete file");
    
   } catch ( Exception $e ) {
    // send error message if you can
   }
  }
 }
 echo '--- ----';
}