Upgrade to 2.1 and db->query doesn't work, can anyone help me with the xPDO

$c = array(
    'contentid' => $docid,
    'tmplvarid' => $tvImageId,
);
$imgTVres = $modx->getCollection('modTemplateVarResource',$c);
$imgTotal_rows = $modx->getCount('modTemplateVarResource',$c);

<?php
$phpThumbOptions = 'w=210&h=220&f=jpg';

// end of settings
$output = '';

if ($modx->user->hasSessionContext($modx->context->get('key')) )
{	
	$user_id       = $modx->user->get('id');
	$tableVars = $modx->getFullTableName('site_tmplvar_contentvalues'); 
	$tvImageId = 21;
	$tvProdDescrId = 20;
	$wishListDocId = $modx->documentIdentifier;	
	
	if (!empty($_GET['deleteId']) and intval($_GET['deleteId']))
	{
		$deleteId = intval($_GET['deleteId']);
		$sql= "DELETE FROM `modx_wishlist` WHERE user_id = {$user_id} AND content_id = {$deleteId} LIMIT 1";
		
		if ($modx->exec($sql))
			$message = 'Item removed from your wishlist';
		else
			$message = 'Can\'t remove this item from your wishlist. Please try later';
			
		$output .= '<div class="message">'.$message.'</div>';
	}
	
	$sql= "SELECT content_id FROM `modx_wishlist` WHERE user_id = {$user_id}";
	if ($stmt = $modx->prepare($sql) 
	and $stmt->execute() 
	and $result = $stmt->fetchAll(PDO::FETCH_ASSOC))
	{
		$output .= '<div>';
		foreach ($result as $n => $val){
			$output .= '<div class="column grid_3 listing">';
			$docId = $val['content_id'];
			$title = ''; $parameters=array(); $imgSrc = ''; $descrSrc = '';

			$parameters = array(
				'id' => $docId,
				'field' => 'pagetitle',
			  );

			$title = $modx->runSnippet('getResourceField',$parameters);
			$title = ($title != '') ? $title : $docId;

			$imgTVres = $modx->db->select('value', $tableVars, "contentid = $docId AND tmplvarid = $tvImageId");
			$imgTotal_rows = $modx->db->getRecordCount($imgTVres);
			if($imgTotal_rows >= 1 ) {
				$row = $modx->db->getRow($imgTVres);
				$imgSrc = $row['value'];
				if ($imgSrc != '') $imgSrc = '<img src='.$modx->runSnippet("phpthumbof",array('input' => $imgSrc, 'options' => $phpThumbOptions)).' title="'.$title.'" class="imgborder"/>';
			}   
  
			$descrTVres = $modx->db->select('value', $tableVars, "contentid = $docId AND tmplvarid = $tvProdDescrId");
			$descrTotal_rows = $modx->db->getRecordCount($descrTVres);
			if($descrTotal_rows >= 1 ) {
				$row = $modx->db->getRow($descrTVres);
				$descrSrc = $row['value']; 
			} 
			$output .= '<h5 class="h5wish"><a href="'.$modx->makeUrl($docId).'">'.$title.'</a></h5>
						  <a href="'.$modx->makeUrl($docId).'"><div class="p-image">'.$imgSrc.'</div></a><br />
						  <div class="p-description"><p>'.$descrSrc.'</p></div>

<a href="'.$modx->makeUrl($docId).'" class="button3"><span id="buttonText">View item</span></a></h5>

<a href="'.$modx->makeUrl($wishListDocId,'','&deleteId='.$docId).'" class="button3"><span id="buttonText">Delete from wishlist</span></a>

				    ';
			$output .= '</div>';
		}
		$output .= '</div>';		
	}
	else
		$output .= 'Your wishlist is empty';
}
else
	$output .= 'Login to view your wishlist';

return $output;