private function insertRecord(string $id, string $key, string $value) : void
    {
        $query = sprintf(
            'INSERT INTO %s (%s, %s, %s, %s) VALUES(?, ?, ?, ?)',
            $this->options['table-name'],
            $this->options['id-column'],
            $this->options['key-column'],
            $this->options['value-column'],
            $this->options['last-access-column']
        );

        $statement = $this->pdo->prepare($query);
        $statement->execute([$id, $key, $value, time()]);
    }