PHP a připojení k databázi

// MYSQL CONNECTION
  $mysql_server = '*****';
  $mysql_user = '*****';
  $mysql_password = '*****';

// MYSQL USER VERIFICATION
  $mysql_verification_database = '*****';
  $mysql1_conn = @mysql_connect ($mysql_server,$mysql_user,$mysql_password);
  $mysql1_db = @mysql_select_db ($mysql_verification_database);

// USER DATABASE ACCESS 
  if(isset($_REQUEST['login']['user']) && isset($_REQUEST['login']['pass'])) {
    if ($mysql1_conn && $mysql1_db) { 
    $cnt['cron_key'] = mysql_result(mysql_query('SELECT COUNT(id) FROM settings WHERE name=\'key\''),0);
      if($cnt['cron_key']==1) {
      $sql['key'] = mysql_fetch_array(mysql_query('SELECT value FROM settings WHERE name=\'key\''));
      $key = $sql['key']['value'];
      }
    $cnt['login_mysql'] = mysql_result(mysql_query('SELECT COUNT(id) FROM users WHERE pass=\''.$_REQUEST['login']['user'].'\' AND login=\''.$_REQUEST['login']['pass'].'\''),0);
      if(!$key) { 
      $error['login'] = 'ERROR 101 - Chyba synchronizace';
      }
      elseif($cnt['login_mysql']==1) {
      $sql['clientdb'] = mysql_fetch_array(mysql_query('SELECT mysql_server, mysql_user, mysql_pass, mysql_database, verification, id FROM users WHERE pass=\''.$_REQUEST['login']['user'].'\' AND login=\''.$_REQUEST['login']['pass'].'\''));
        if($sql['clientdb']['ip']==0) {
        $_SESSION['uniadczadmin']['id'] = $sql['clientdb']['id'];
        $_SESSION[$key]['connection'] = @mysql_connect($sql['clientdb']['mysql_server'],$sql['clientdb']['mysql_user'],$sql['clientdb']['mysql_pass']);
        $_SESSION[$key]['db'] = @mysql_select_db($sql['clientdb']);
        $_SESSION[$key]['mysql_database'] = $_SERVER['REMOTE_ADDR'];
        $_SESSION[$key]['id'] = $sql['clientdb']['id'];
        $save_time = time();
        $_SESSION[$key]['time'] = $save_time;
        $query['insert_access'] = mysql_query('INSERT INTO access (id_client,time,ip,key) VALUES (\''.$sql['clientdb']['id'].'\',\''.$save_time.'\',\''.$_SERVER['REMOTE_ADDR'].'\',\''.$key.'\')');
          if($query['insert_access']) {
           $done['login'] = 1;
          }
        }
        else {
        $error['login'] = 'IP adresa '.$_SERVER['REMOTE_ADDR'].' není pro tento účet povolena';
        }
      }
      else {
      $error['login'] = 'Špatné přihlašovací údaje';
      }
    }
    else {
    $error['login'] = 'ERROR 102 - Chyba synchronizace';
    }                                                                           
  }