public function quoteIdentifier($value)
    {
        if ($value instanceof Expr) {
            return $value->getValue();
        }

        if ($value === '*') {
            return $value;
        }

        $pieces = explode('.', $value);

        foreach ($pieces as $key => $piece) {
            $pieces[$key] = '`'.$piece.'`';
        }

        return implode('.', $pieces);
    }