我是一个初学者，我正在寻找一个多小时的解决方案，我没有时间浪费这个周末。
所以我想有日期，目的地和名字，其中klant\u code=reis\u code，但我得到的错误显示在我的标题。如果我使用

select klant.naam, reis.bestemming from klant,reis where klant_code = reis_code

它的工作，我不明白的是，它得到的错误，只有当我想添加日期的klant（客户端）。我做错什么了？
谢谢你的时间和帮助！这是我的sql代码：

CREATE TABLE `bestelling` (
  `bestelling_code` int(11) NOT NULL,
  `klant_code` int(11) NOT NULL,
  `reis_code` int(11) NOT NULL,
  `datum` date NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

--
-- Gegevens worden geëxporteerd voor tabel `bestelling`
--

INSERT INTO `bestelling` (`bestelling_code`, `klant_code`, `reis_code`, `datum`) VALUES
(1, 1, 1, '2017-12-12'),
(2, 5, 3, '2018-01-01'),
(3, 2, 5, '2018-03-05'),
(4, 4, 2, '2018-08-08'),
(5, 3, 4, '2018-12-10');

-- --------------------------------------------------------

--
-- Tabelstructuur voor tabel `klant`
--

CREATE TABLE `klant` (
  `klant_code` int(11) NOT NULL,
  `naam` varchar(20) NOT NULL,
  `adres` varchar(20) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

--
-- Gegevens worden geëxporteerd voor tabel `klant`
--

INSERT INTO `klant` (`klant_code`, `naam`, `adres`) VALUES
(1, 'Gester', 'Amsterdam'),
(2, 'Piet', 'Breda'),
(3, 'Klaas', 'Rotterdam'),
(4, 'Henk', 'Etten-leur'),
(5, 'Sjaak', 'Tilburg');

-- --------------------------------------------------------

--
-- Tabelstructuur voor tabel `reis`
--

CREATE TABLE `reis` (
  `reis_code` int(12) NOT NULL,
  `bestemming` varchar(12) NOT NULL,
  `klasse` int(11) NOT NULL,
  `prijs_in_euro` int(11) NOT NULL,
  `geannuleerd` tinyint(1) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

--
-- Gegevens worden geëxporteerd voor tabel `reis`
--

INSERT INTO `reis` (`reis_code`, `bestemming`, `klasse`, `prijs_in_euro`, `geannuleerd`) VALUES
(1, 'Spanje', 1, 500, 1),
(2, 'Duitsland', 2, 300, 0),
(3, 'Griekenland', 2, 700, 1),
(4, 'Italie', 1, 640, 0),
(5, 'Belgie', 2, 80, 1);
COMMIT;

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