MySQL 1241错误

Question

我有两个独立的查询，这是计算总进出额的付款为一个给定的节日。IN/OUT由ENUM值提供(见下文)。

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如果我独立运行这些查询，它将根据所选的payment_type输入或输出给出正确的SUM输出。我的问题是，当我试图将它们合并到一个查询中，以便为IN/OUT创建两个单独的列时，如下所示。

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我在MySQL中有错误“操作数应该包含1列”。在我做了一些研究之后，我相信子查询是错误的，但我不太确定如何解决它。

谢谢你的帮忙..。

总IN

SELECT
    SUM(`payment`.`pmt_amount`) AS `TOTAL IN`
    , `payment`.`pmt_type`
    , `festival`.`id_festival`
FROM
    payment
    INNER JOIN festival
        ON (`payment`.`id_festival` = `festival`.`id_festival`)
WHERE (`payment`.`pmt_type` LIKE '%IN'
    AND `festival`.`id_festival` = 1);

​

​

然后完全消失

SELECT
    SUM(`payment`.`pmt_amount`) AS `TOTAL OUT`
    , `payment`.`pmt_type`
    , `festival`.`id_festival`
FROM
    payment
    INNER JOIN festival
        ON (`payment`.`id_festival` = `festival`.`id_festival`)
WHERE (`payment`.`pmt_type` LIKE '%OUT'
    AND `festival`.`id_festival` = 1);

​

​

组合

SELECT
  festival.id_festival,
  payment.pmt_amount,
  payment.pmt_type,
  (SELECT
      payment.pmt_type,
      SUM(payment.pmt_amount) AS `TOTAL OUT`
    FROM payment
    WHERE payment.pmt_type LIKE '%OUT'),
  (SELECT
      payment.pmt_type,
      SUM(payment.pmt_amount) AS `TOTAL IN`
    FROM payment
    WHERE payment.pmt_type LIKE '%IN')
FROM payment
  INNER JOIN festival
    ON payment.pmt_amount = festival.id_festival
WHERE festival.id_festival = 1

​

​

Answer 1

您可能只想在这里使用条件聚合：

SELECT
    f.id_festival,
    SUM(CASE WHEN p.pmt_type = 'Payment IN'  THEN p.pmt_amount ELSE 0 END) AS `TOTAL IN`,
    SUM(CASE WHEN p.pmt_type = 'Payment OUT' THEN p.pmt_amount ELSE 0 END) AS `TOTAL OUT`
FROM festival f
INNER JOIN payment p
    ON p.id_festival = f.id_festival
WHERE f.id_festival = 1
GROUP BY
    f.id_festival;

请注意，您的查询只查看一个节日，但是正确的表达方式是通过GROUP BY，即使我们只想在输出中保留一个组。

Answer 2

您的子查询必须返回only one column，但是您的查询正在返回two column，这是错误的，请尝试在下面提到查询：

SELECT
  festival.id_festival,
  payment.pmt_amount,
  payment.pmt_type,
  (SELECT
      SUM(payment.pmt_amount) AS `TOTAL OUT`
    FROM payment
    WHERE payment.pmt_type LIKE '%OUT') AS `TOTAL OUT`,
  (SELECT
      SUM(payment.pmt_amount) AS `TOTAL IN`
    FROM payment
    WHERE payment.pmt_type LIKE '%IN') AS `TOTAL IN`
FROM payment
  INNER JOIN festival
    ON payment.pmt_amount = festival.id_festival
WHERE festival.id_festival = 1