protected function isBelongsToMany($foreignKey)
    {
        $remote = $this->describes[$foreignKey->TABLE_NAME];
        $count = 0;
        foreach ($remote as $field) {
            if ($field->Key == 'PRI') {
                $count++;
            }
        }
        if ($count == 2) {
            return true;
        }

        return false;
    }