Bitrix(d7). DB query

d7.php

<?php
use Bitrix\Main\Application;

$connection = Application::getConnection();
$sqlHelper = $connection->getSqlHelper();

$sql = "SELECT ID FROM b_user WHERE LOGIN = '".$sqlHelper->forSql($login, 50)."'";

//$connection->query($sql, $limit);
//$connection->query($sql, $offset, $limit);
$recordset = $connection->query($sql);
while ($record = $recordset->fetch())
{
  //do something
}

//---------------
$recordset->addFetchDataModifier(
   function ($data)
   {
       $data["NAME"] .= "!";
       return $data;
   }
);

while ($record = $recordset->fetch(\Bitrix\Main\Text\Converter::getHtmlConverter()))
   {
      $data[] = $record;
   }
//------------


$cnt = $connection->queryScalar("SELECT COINT(ID) FROM table");

$connection->queryExecute("INSERT INTO table (NAME, SORT) VALUES ('Название', 100)")

old.php

<?php 
global $DB;
$sql = 'SELECT * FROM table';
$res = $DB->Query($sql, false,"<b>Error in </b><br/>File: ".__FILE__."<br/>Line: ".__LINE__."<br/>");
//$res->fetch()