should::extractPrimaryIndexes

static function extractPrimaryIndexes($data)
{
	$result = array();

	if (!is_array($data))
	{
		return $result;
	}

	if(static::getIsMultiple())
	{
		if(is_array($data))
		{
			foreach($data as $item)
			{
				$result[] = static::extractPrimaryIndex($item);
			}
		}
	}
	else
	{
		$result[] = static::extractPrimaryIndex($data);
	}

	return $result;
}